Correct....... anything plugged into the J234 other than CAN High/Low for COM & Terminals 15, 30 and 31 to power the unit.
Isolate the J234 & yourself from the rest like I do first.........
Use VCDS when initiating COM........ this way no DVOM or test light testing FUBAR, to make a BAD day worse, go boom or by mistake by using alligator clips to shunt/bridge preventing static charge for each component & verify block values in VCDS to do what the module needs or to see until circuit is indeed detected.
Prepare to bifurcate!
Do it at the controller one circuit at a time & between each test for COM with VCDS and once you find it, than it's harness or component!
I hope you checked every fuse?
Okay well I'll go through the fuses once more and make sure there are none missing as well.
To finally confirm here, I'll be disconnecting said wires from the connector for the airbag module? It's a big yellow connector with a hard bend in all of the wires as they enter the plastic connector area. I'm not sure of the logistics of taking out and reconnecting each of these wires.