DHCP Client unicast vs broadcast

I’ve been using an RB2011with a 75Mb/s FTTH service (Verizon FiOS) since it came out, and been pretty happy with it, but doing more multi-site IPSEC recently and decided to upgrade to an RB1100AHX2. After getting all my settings nailed down, cloning the MAC over for the WAN port, I tried a switchover, and got no response to the DHCP requests.

Digging further, I ran a packet capture on the WAN port of the RB1100 (running 6.35.4), and compared to a capture on WAN of the RB2011 (running 6.35.2), and the ONLY difference in the DHCP request was the RB2011 sending unicast, while the RB1100 sends as broadcast. I checked a stock Verizon router, it also uses unicast, and there are references on some forums to them being ‘finicky’ about DHCP requests - I had to spoof the DHCP hostname as ‘FIOS_Quantum_Gateway’ even after they flushed their cache, so they really want you to use their router. Wireshark dissection below

Is there any way to force the RB1100 to use unicast?

RB2011 (works):

Frame 3: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits)
Ethernet II, Src: VerizonB_a5:5b:19 (c8:a7:0a:a5:5b:19), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 0.0.0.0, Dst: 255.255.255.255
User Datagram Protocol, Src Port: 68 (68), Dst Port: 67 (67)
Bootstrap Protocol (Discover)
    Message type: Boot Request (1)
    Hardware type: Ethernet (0x01)
    Hardware address length: 6
    Hops: 0
    Transaction ID: 0x93716715
    Seconds elapsed: 20
    Bootp flags: 0x0000 (Unicast)
        0... .... .... .... = Broadcast flag: Unicast
        .000 0000 0000 0000 = Reserved flags: 0x0000
    Client IP address: 0.0.0.0
    Your (client) IP address: 0.0.0.0
    Next server IP address: 0.0.0.0
    Relay agent IP address: 0.0.0.0
    Client MAC address: VerizonB_a5:5b:19 (c8:a7:0a:a5:5b:19)
    Client hardware address padding: 00000000000000000000
    Server host name not given
    Boot file name not given
    Magic cookie: DHCP
    Option: (53) DHCP Message Type (Discover)
        Length: 1
        DHCP: Discover (1)
    Option: (55) Parameter Request List
        Length: 7
        Parameter Request List Item: (1) Subnet Mask
        Parameter Request List Item: (121) Classless Static Route
        Parameter Request List Item: (3) Router
        Parameter Request List Item: (33) Static Route
        Parameter Request List Item: (6) Domain Name Server
        Parameter Request List Item: (42) Network Time Protocol Servers
        Parameter Request List Item: (138) CAPWAP Access Controllers
    Option: (61) Client identifier
        Length: 7
        Hardware type: Ethernet (0x01)
        Client MAC address: VerizonB_a5:5b:19 (c8:a7:0a:a5:5b:19)
    Option: (12) Host Name
        Length: 20
        Host Name: FIOS_Quantum_Gateway
    Option: (255) End
        Option End: 255
    Padding: 00000000000000000000000000000000

RB1100 (no response from ISP):

Frame 3: 342 bytes on wire (2736 bits), 342 bytes captured (2736 bits)
Ethernet II, Src: VerizonB_a5:5b:19 (c8:a7:0a:a5:5b:19), Dst: Broadcast (ff:ff:ff:ff:ff:ff)
Internet Protocol Version 4, Src: 0.0.0.0, Dst: 255.255.255.255
User Datagram Protocol, Src Port: 68 (68), Dst Port: 67 (67)
Bootstrap Protocol (Discover)
    Message type: Boot Request (1)
    Hardware type: Ethernet (0x01)
    Hardware address length: 6
    Hops: 0
    Transaction ID: 0xa1fb40f1
    Seconds elapsed: 38
    Bootp flags: 0x8000, Broadcast flag (Broadcast)
        1... .... .... .... = Broadcast flag: Broadcast
        .000 0000 0000 0000 = Reserved flags: 0x0000
    Client IP address: 0.0.0.0
    Your (client) IP address: 0.0.0.0
    Next server IP address: 0.0.0.0
    Relay agent IP address: 0.0.0.0
    Client MAC address: VerizonB_a5:5b:19 (c8:a7:0a:a5:5b:19)
    Client hardware address padding: 00000000000000000000
    Server host name not given
    Boot file name not given
    Magic cookie: DHCP
    Option: (53) DHCP Message Type (Discover)
        Length: 1
        DHCP: Discover (1)
    Option: (55) Parameter Request List
        Length: 7
        Parameter Request List Item: (1) Subnet Mask
        Parameter Request List Item: (121) Classless Static Route
        Parameter Request List Item: (3) Router
        Parameter Request List Item: (33) Static Route
        Parameter Request List Item: (6) Domain Name Server
        Parameter Request List Item: (42) Network Time Protocol Servers
        Parameter Request List Item: (138) CAPWAP Access Controllers
    Option: (61) Client identifier
        Length: 7
        Hardware type: Ethernet (0x01)
        Client MAC address: VerizonB_a5:5b:19 (c8:a7:0a:a5:5b:19)
    Option: (12) Host Name
        Length: 20
        Host Name: FIOS_Quantum_Gateway
    Option: (255) End
        Option End: 255
    Padding: 00000000000000000000000000000000