I'm not sure what the problem is, but if it is stopping you bridging the physical interface effectively, could you not define a virtual bridge with local only a

I'm not sure what the problem is, but if it is stopping you bridging the physical interface effectively, could you not define a virtual bridge with local only addresses and have the host NAT to/from that and the physical interface? Adds a little extra latency to be sure, more so if you have two or more boxes on the same network with containers that would otherwise talk directly to each other on a private vlan, but if your physical box is being a firewall/router for the tasks in the containers anyway it is already practically doing the job.