Need some help 1812 fans.

I have a column of lights out on the playfield that I just can't figure out. The column in question is the very first in the lamp matrix with the Shoot Again, Bottom LED on the bat sign, and all the way down that column.
I have gone through Caly's guide on system 3 pertaining to this and I know lamps and switches are connected in the switch matrix. However, All of the switches in that column work fine: The 3 left bank standups, the right ramp opto, the coin switches; all in the switch column matrix work fine.
I checked all the transistors on the driver board, but they all test good.
I checked the diode boards under the playfield too and those all test good.
So, the only other thing I can think of is a shorted lamp socket? putting a continuity test to a few (grave, droor prize and one of the Zom B's lights) I get connectivity from the tab to the base. To be sure, I replaced every socket in that column with no success.
If anyone has some insight to this, please let me know.

anyone?

Bump

Maybe someone has some suggestions?

still looking for answers...