Topic: NES just cooked one of my games!?

I was playing Millipede on an old toaster NES. It started to glitch out like crazy, scores skyrocketing into the 200,000s. I took the game out and...the contacts smelled like burning plastic. The cartridge slot smells like burning. I unplugged the AC adapter. Just to be sure, I smelled the AC port and it also smells like cooked electronics.

I have the unit unplugged as of now. I shined a flashlight inside. There doesn't appear to be any sign of blackening or warping, but that smell is strong as ever in there. It is horrendous. Of the worst smells I've ever experienced. It's got my throat hurting this morning.

So I'm wondering, did the AC adapter malfunction? Does a toaster NES become a literal toaster after however many years this one has been active (I bought it from a used game place for around $60?) Is it safe to use this NES anymore or does it need to be scrapped?

EDIT: Not sure if this helps, but the AC adapter is an original NES one, model NES-002.