Seems like you've changed just about every IC to do with the lamp matrix.    At times like these it would be nice to have a spare board to throw into the thing.

Anyway, if I am correct when you single lamp test the "I" in KISS with only the row 2 jumped to the driver board it lights the 30 million in row 7 as well. If this is the case then as you have disconnected the board ground from row 7 it may be picking up a ground from somewhere else. Possibly from row 2. Have you used a multimeter to check for shorts between row 2 and 7 or  row 2 and 4 in the field wiring. Just a theory....


PS: You may already know these useful sites for fault finding. They have help me heaps in the past.
http://pinballrehab.com/1-articles/solid-state-repair/repair-guides/148-lamp-matrix-theory-and-troubleshooting



http://techniek.flipperwinkel.nl/wpc/index2.htm#remove