A few switches in the same matrix row (here the left VUK switch and an outlane rollover among them) never register in switch test, while the other switches in that row work.

Several switches in one row dead but others work: loose daisy-chain wire

Cause: The row wire is daisy-chained from switch to switch under the playfield. It had come loose at one of the switches that still worked, cutting off the switches further down the chain.

Checks

• Use the switch matrix chart to confirm the dead switches share a row.
• Follow the row wire from switch to switch under the playfield, including through the working ones, and look for a loose or broken joint.
• Jumpering across a dead switch's lugs shows whether its wiring back to the board is intact.

Fix

• Resolder the loose wire at the switch where the chain is broken.

Games

• Striker Xtreme

Source: Pinball Repair help group!! (Facebook group)