Hello, and welcome!
Disclaimer: I don't use VLANs, but I do use queues and carp interfaces.
The
pf.conf(5) man page has examples of filter rules on VLAN interfaces.
vlan(4) devices are not the same as carp(4) devices, and even though both are virtual they should be treated differently. Based solely on that, I would recommend testing your queue assignments without reference to the specific interfaces at all. The man page states that
on <interface> is optional.