Have you checked for a blown fuse? If they’re all intact I would try to clear all faults, run basic settings on that module, ignition off for 30 seconds and back on.
I haven’t read the repair info for that specific model but it’s worth a try. Otherwise you’d need to download the repair docs...
Databus and terminal 15 errors on your gateway suggest some of the car’s loom may still be damaged. I would personally check if any wires have welded together and continuity test them all using a proper wiring diagram. Also check plugs have got proper clean connections
If the right module works on the left side then the issue is probably paramaterisation. What is the difference with the other module you are trying?
VCDS can’t help with parameterisation, you’ll need to use another forum
18698 - Left LED Module for DRL and Parking Lights
B12EC F2  - Voltage Supply Open or Short to Plus
Confirmed - Tested Since Memory Clear
U1326 00  - No Communication