What did I do?
what could be causing a fault in a new set of catalytic converters? injector slobber? Bad sensors? bad vag-com? hobbits living in the crankcase?

What kind of converters were installed? OEM or aftermarket? It's possible that if they were welded in the welder fried one of the post-cat O2 sensors, it happened on my car when I switched cats.

They were purchased through autoparts warehouse.com made by DEC.
Is there a way to test the sensors?

What am I looking for in resistance and ohmage?

Bank 1 does not have a problem and I changed both cats. Seems like I would have two faults rather than 1 if it were the cats.

My suspicion is sensors in bank 2.

can you tell me how to test the sensors after I take them out? Can't imagine brand new $250.00 cats that are bad...
Do the sensors go bad when they get hot?
The engine overheated ... cats were tested at the shop as bad, and replaced them.

Not sure exactly what that is, but it is outlined clearly in the manual.