This is very long-shot guess but based on the comment in config, I understand your Ether2 might have something to do with VLAN .. can you confirm/deny whether Ether2 receives (and passes to the bridge) tagged frames? If there are VLAN tags involved, where do you add/strip tags?
I think that might change the situation a lot: Firstly, AP is not configured for VLANs, secondly, I recently identified situation, when CHR does not bridge VLAN tagged frames correctly and despite internal packet sniffer saying it see the packet, it does not actually pass from bridge into virtual ethernet adapter. This might be similar case…