I'd start by looking at the switch matrix in your manual. How are all the switches related? Same row or column?

I would test other switches in that row. The green-yellow wire is probably broken at one of them. 50 or 51 seem likely suspects.

yes. exactly. They go to each switch and back to the main board. You can meter out the wire with a DMM but first physically check each switch looking for broken pinched or bad wiring.
I have a WPT too so let me know if u need help.
Cheers

And if there is a break it takes everything out down stream of that connecction.[Makes them not work] Easy to track down. No sweat.

If EVERY switch in the row is out then you probably have the green-yellow wire pulled out of the connector at J1-pin 5. But could also be the drive transistor Q4 I suppose.
An excellent switch matrix troubleshooting guide is located at https://pinballrehab.com/1-articles/solid-state-repair/repair-guides/146-switch-matrix-theory-and-troubleshooting#row-failure
At the end of that article it describes how to disconnect your playfield and test the board. If your board tests good you know it's a broken wire somewhere.

I thought from reading your first post that the first couple of the row four switches were working.