Damage risk is low since we are dealing with grounds here, but my worry is false continuity readings through the ECU throwing off what you are trying to chase down.
I do have a spare A9L on the shelf. I can confirm in a bit that 30 and 46 are normally open.
Update - codes are fixed!
After getting some good advice here I spent the weekend testing continuity to and from the ECU and the various switches shown in the diagram.
However, what is not shown in the diagram is that pin 30 also connects to the o2 harness, where there is a jumper wire that loops back into itself in few different ways for either a t5 or AOD transmission.
That is why some people had a code 67 after swapping T5 to AOD, or vice versa.
I tested everything there and it seemed ok, so I reconnected and pulled the codes again just out of curiosity.
no code 67!
I should also mention the reason why it was so important for me to get rid of code 67, this code will prevent you from running KOER tests, which I needed to do test and eliminate some other issues I was having (code 41/91, lean readings at both o2 banks)
Well, after reconnecting the o2 harness, not only was code 67 cleared, but the o2 codes were gone as well!
I have determined that although the o2 harness was connected, it was not fully seated to the point where the clip would lock it together, and therefore the connections were not 100% and sending inconsistent signals back to the ECU.
Big thanks to anyone who posted here to help, as going through the process of recommendations I received is what led me to this fix.
Glad to be back out on the road with confidence.