One of the queues in my interface queue tree doesn't work

I am setting up QOS using a queue tree on the WAN interface (upload) and a queue tree on the LAN interface (download). I have the following setup:

/interface bridge settings set use-ip-firewall=yes
/interface bridge settings set use-ip-firewall-for-vlan=yes

/ip firewall address-list add address=192.168.200.0/24 list=wifi-guest

/interface bridge add name=lan protocol-mode=none
/interface bridge port add bridge=lan interface=ether7
/interface bridge port add bridge=lan interface=ether2
/interface bridge port add bridge=lan interface=ether3
/interface bridge port add bridge=lan interface=ether4
/interface bridge port add bridge=lan interface=ether5
/interface bridge port add bridge=lan interface=ether6
/interface bridge port add bridge=lan interface=combo1

/ip address add address=192.168.1.254/24 interface=lan
/interface vlan add interface=ether7 name=wifi-guest vlan-id=200
/ip address add address=192.168.200.254/24 interface=wifi-guest

/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=wifi-guest passthrough=no src-address-list=wifi-guest
/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=backblaze  passthrough=no dst-address-list=backblaze
/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=http       passthrough=no protocol=tcp dst-port=80,443
/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=usenet     passthrough=no protocol=tcp dst-port=563
/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=dns        passthrough=no protocol=tcp dst-port=53
/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=dns        passthrough=no protocol=udp dst-port=53
/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=tos        passthrough=no protocol=tcp dst-port=7001,7002
/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=tos        passthrough=no protocol=udp dst-port=7001,7002
/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=ssh        passthrough=no protocol=tcp dst-port=22
/ip firewall mangle add chain=forward action=mark-connection out-interface=wan connection-mark=no-mark new-connection-mark=icmp       passthrough=no protocol=icmp

/ip firewall mangle add chain=postrouting action=mark-packet connection-mark=http       new-packet-mark=http       passthrough=no
/ip firewall mangle add chain=postrouting action=mark-packet connection-mark=ssh        new-packet-mark=ssh        passthrough=no
/ip firewall mangle add chain=postrouting action=mark-packet connection-mark=wifi-guest new-packet-mark=wifi-guest passthrough=no
/ip firewall mangle add chain=postrouting action=mark-packet connection-mark=usenet     new-packet-mark=usenet     passthrough=no
/ip firewall mangle add chain=postrouting action=mark-packet connection-mark=backblaze  new-packet-mark=backblaze  passthrough=no
/ip firewall mangle add chain=postrouting action=mark-packet connection-mark=dns        new-packet-mark=dns        passthrough=no
/ip firewall mangle add chain=postrouting action=mark-packet connection-mark=tos        new-packet-mark=tos        passthrough=no
/ip firewall mangle add chain=postrouting action=mark-packet connection-mark=icmp       new-packet-mark=icmp       passthrough=no

/queue tree add name=upload        parent=wan    max-limit=35M queue=fair
/queue tree add name=up_prio1      parent=upload max-limit=35M limit-at=1M  queue=low-latency priority=1 packet-mark=dns,icmp   comment="Prio 1 (highest) traffic"
/queue tree add name=up_prio2      parent=upload max-limit=35M limit-at=1M  queue=fair        priority=2 packet-mark=tos        comment="Prio 2 traffic"
/queue tree add name=up_prio3      parent=upload max-limit=35M limit-at=10M queue=fair        priority=3 packet-mark=ssh        comment="Prio 3 traffic"
/queue tree add name=up_prio4      parent=upload max-limit=35M limit-at=10M queue=fair        priority=4 packet-mark=http       comment="Prio 4 traffic"
/queue tree add name=up_wifi-guest parent=upload max-limit=3M  limit-at=1M  queue=fair        priority=5 packet-mark=wifi-guest comment="Wifi-guest traffic"
/queue tree add name=up_prio6      parent=upload max-limit=35M limit-at=7M  queue=fair        priority=6 packet-mark=no-mark    comment="Prio 6 traffic"
/queue tree add name=up_prio7      parent=upload max-limit=35M limit-at=4M  queue=fair        priority=7 packet-mark=usenet     comment="Prio 7 traffic"
/queue tree add name=up_prio8      parent=upload max-limit=35M limit-at=1M  queue=fair        priority=8 packet-mark=backblaze  comment="Prio 8 (lowest) traffic"

/queue tree add name=download      parent=lan      max-limit=1000M queue=fair
/queue tree add name=dn_prio1      parent=download max-limit=1000M limit-at=10M  queue=low-latency priority=1 packet-mark=dns,icmp   comment="Prio 1 (highest) traffic"
/queue tree add name=dn_prio2      parent=download max-limit=1000M limit-at=10M  queue=fair        priority=2 packet-mark=tos        comment="Prio 2 traffic"
/queue tree add name=dn_prio3      parent=download max-limit=1000M limit-at=100M queue=fair        priority=3 packet-mark=ssh        comment="Prio 3 traffic"
/queue tree add name=dn_prio4      parent=download max-limit=1000M limit-at=100M queue=fair        priority=4 packet-mark=http       comment="Prio 4 traffic"
/queue tree add name=dn_wifi-guest parent=download max-limit=50M   limit-at=5M   queue=fair        priority=5 packet-mark=wifi-guest comment="Wifi-guest traffic"
/queue tree add name=dn_prio6      parent=download max-limit=1000M limit-at=100M queue=fair        priority=6 packet-mark=no-mark    comment="Prio 6 traffic"
/queue tree add name=dn_prio7      parent=download max-limit=1000M limit-at=50M  queue=fair        priority=7 packet-mark=usenet     comment="Prio 7 traffic"
/queue tree add name=dn_prio8      parent=download max-limit=1000M limit-at=10M  queue=fair        priority=8 packet-mark=backblaze  comment="Prio 8 (lowest) traffic"

Every queue is working perfectly, except the wifi-guest download queue. Even the wifi-guest upload queue is working correctly. I’ve verified that the wifi-guest packets are getting marked. But there are no packets going through the wifi-guest download queue. I am not using fasttrack. Can anyone clue me in as to why this one specific queue is not working?

EDIT: I’m guessing this has something to do with ether7 being in both the lan bridge and the wifi-guest vlan. But I’m putting the queues on the logical interfaces, not the physical interface. Shouldn’t that work?

If I’m not mistaken your wifi download traffic leaves over vlan interface not over lan interface.
But your wifi download is attached to download which is attached to lan.

Attach the wifi-download queue to vlan interface.

I was hoping I was missing something simple, and indeed, I was. Thanks much.