What type of cap devices are you using. My cap ACs have two ethernet ports but only use one (wired connection to it)?
(It is by no means a switch but I suppose if desperate…)
Do you have datapath set to local-forwarding=no? In this case there’s actually a tunnel between cap and capsman and all traffic flows there. So no VLANs on caps, everything is done by capsman. This kind of setup is fine as you don’t need any configuration on caps at all. But has (at least) two drawbacks: a) induces higher load on capsman as it has to deal with all traffic of all connected caps and b) leaves other interfaces on cap devices essentially unusable. Alternative is to configure cap devices with appropriate LAN config (VLANS, interfaces, IP setup, …) and create datapath with local-forwarding=yes and appropriate vlan settings (vlan-id and vlan-mode) as if wireless was configured without capsman.