Hi all, have a lingering switch/opto issues with my BSD.

I've been trying to get this BSD fully working for awhile and am stumped. My issue is that switch 77 (R Ramp Up) when pressed, triggers ALL of column 5. Switch 77 is a physical switch where 7 of 8 of the switches on column 5 are optos. I have replaced the switch and its diode and have tested the actual switch in other areas of the machine and it only triggers once when connected to other switch wiring in the game. The machine has a new MPU as well as a new 10 opto board. I verified that J207 on the MPU is wired and connected correctly. J207 is clean with no previous acid damage. I've tested all of column 5 and each opto and switch triggers properly in test mode. Not sure where to go from here...

I appreciate any help!

Some updated info. Per a suggestion from a friend, I disconnected switch 57 (Castle lock 3 opto) and when doing so, switch 77 then activates normally. I checked the 3 castle lock optos and they all test normally when connected and the opto transmitter/receiver boards all look good. Should I just go ahead and redo the connectors going to the 10 opto board at this point?