OK, so it seems that leaving the PVID blank puts it on VLAN 1 (as it's supposed to).
That guest VLAN will most likely NOT be able to print to a local printer, since it seems that subnet / ip address whitelisting was removed in the 5.x controller.
As for everything else - there doesn't seem to be anything in the setup that's blocking it. Most likely you've got a setting on the printer itself (e.g. only allow jobs from 192.168.7.x), or software firewalls on the machines are in the way.
