Dungeons and Dragons deep dive troubleshooting 2 switch issues

A long distance customer has an unusual set of symptoms on his DnD LE so I will walk him through my ideas of what might be happening, how to run tests, and what to look for underneath the playfield. 1. His right inlane switch isn't working. It may be a simple problem with the switch or it may be a break in the ground wire chain so we'll look at both. 2. When he shoots the ball into the dungeon during gameplay, the game serves and launches a second ball into play, which shouldn't happen. The dungeon mech causes a lot of vibration so I walk through some theories about various switches that would cause the game to serve another ball such as the cube, outlane switches, the main trough, or the dragon trough. This video may help if you're wondering how to troubleshoot confusing switch issues on Stern Spike 2 games. It shows how to reference the manual for wire colors and related switches. Let me know if you have ever seen this problem or if you have more suggestions.