I mean it sounds like it could be video from the charging facility

I mean that’s what I assumed. I can’t imagine a reason one would want a camera watching you charge - like that’s an expense for little if any benefit. And if it was charged at a charging station owned by Tesla, I would be shocked if there wasn’t camera footage or if Tesla didn’t have access to it.

but what the actual fuck they can unlock your car.

I would imagine any car with keyless entry can be unlocked by the manufacturer if they have your VIN. They build the system and pair the keyfobs and locks, they’re bound to have that ability in case something happens to your keys.