Wow, bummer. Sorry to hear about that! The units may still be salvageable, but if the built-in circuit breakers and/or fuses didn't blow than you might have some deeper repairs to do. Same process - just start swapping parts between a good light and a bad one, though a multimeter or o-scope can help to speed up the diagnostics if you suspect a failure at the component level.
Sounds like you had some non-conforming power problems too. Volunteers can be great for manual labor and whatnot (and we all started somewhere), but I've learned that some need more guidance and supervision than others, especially when you have ones that kinda sorta think they know what they're doing... Too much expensive equipment on the line, not to mention liability. It's one thing for someone to goof running a sound or light board, but it's a whole other issue to mess up electrical or rigging. Those things go very bad very fast! A lesson learned though is to always meter your power before plugging in! Best of luck trying to sort this all out!
