This should help.

I think it's out of a Stern manual, but not positive. The row and column wires are daisy chained so all except the last switch in each row/column will have two wires on each tab. So yes, I would think both wht/grn wires go to that tab or the chain would get broken.

That's a good philosiphy, but the good news is that nothing can go bad from having them together. The worst case is that some other switch would not work, and based on the fact they were tied together I doubt that.

Game off, check the switch with a DMM in diode/continuity. When you close the switch does it beep? Then check the row and column wires at the switch to another switch in the same row and the same column (two tests). Make sure everything is wired per the diagram above.

As far as I can tell the wiring looks correct.

So right now you're saying the switch does not register? If that is the case then check from the wht-grn wire to the wht-grn wire on a switch that does work. Also check from the grn-blk wire to the grn-blk wire on a switch that does work.

When testing the switch NC to com should beep when the switch is open and NO to com should beep when the switch is closed.

Glad you got it working.