What davenn said.
Can't tell much from what we can see, but it looks like your power transformer is still there, that's good. The bad part is that you mentioned burn marks under one of the boards. You'll probably be able to see a damaged
electronic component or components on the board directly above the burn marks (or at least ones showing signs of excessive heat).
I'm wondering if your two red wires were connected to some lighting device for your fancy cabinet, that somebody removed.
I can't tell from your third picture if the transformer (with two red wires), was then connected to the two yellow wires of the nearby circuit board.
Having worked in TV & radio repair shops years ago, I'll offer speculation here: Something on the 'burn-mark' board died and the unit stopped working. Somebody decided that a light or other decorative device looked nice,
and cut it out of the unit to use elsewhere. We'll need more pictures (clear), to narrow this down. But I THINK your primary problem is going to be the 'burn-marked' board, and the open yellow and red wires are a peripheral
problem that will be easily sorted-out. Don't give-up on this yet.