Smartkey ECU to door receiver wiring - keyfob issue

In my 2008 Prius, I have the "SKS keyfob not recognized" problem (including the button press in the fob not recognized) for past several weeks. It works to start the car while in the slot after entering manually via key slot open. I read several posts and wanted to disconnect 12v battery and connect to get it going (some folks have found this work). When I opened the trunk area I noticed water at the bottom of battery and tire area and some moisture in the driver side hatch area beneath the trim panel. I emptied and dried most of the area I could reach. Since, the 12v disconnect step didn't make any difference (yellowtop optima less than 4 year old), I have now installed a new 12v battery (battery tests ok with multimeter and MFD). Changed brand new cr2032 (measures 3.13v) in both they silver fobs that came with purchase (red led on fob illuminate on the key press - no issues with any button like panic being stuck ). No issues like cellphone or other interferences. Also, the 'key' button under steering wheel is in the proper position (out). None of these seem to solve the issue.

After several searches, I stumbled upon a thread, in which op had similar context (no issues with 12v, cr2032 battery) and he/she indicated the real issue being the violet wire damage from receiver.

Quoting the crux of the diagnosis from the OP's observation

OP indicated a wiring issue due to moisture, it rang a bell since, I had moisture issue due to the infamous 'roof crack leak'!

I understand that the ECU module in the trunk area, but, I am not very sure on which area/wire to check to locate the 'violet' wire leading to door receiver that the OP was referring to. I would like get help on the Smartkey ECU to door receiver wire that OP is talking about. Any pics or links on this topic?