You may need to provide a complete network diagram showing what all is going where...If you set the access port VLAN to 43, on the wired profile of the mesh point, what does the wired port for the corresponding mesh portal look like? Is it also bridged and does it specifically include VLAN 43 in it's config? If the portal in VLAN 43 as well, or is it in another VLAN? If another VLAN, is the switch port the portal configured on set to trunk with native VLAN whatever for the portal and has added the trunk port on VLAN 43, and does the mesh portal's point also configured that way (trunk port native whatever, trunk port allow vlan 43)?
You're running it in bridge mode, which means you need L2 continuity from the point to portal wired interfaces. If not, there's no layer 2. You can try to put the mesh point's wired interface as access vlan 43 and put it in TUNNEL mode. At that point, the mesh point will build a GRE tunnel from the point to the controller. That will more closely mimic the behavior of the wireless VLAN 43 traffic working.