Seems like just about everyone has a video doorbell and/or other cameras monitoring their property. Took it for granted in my youth without even knowing it.
I would actually be kind of proud of my kids if they threw a successful party with their friends when I was out of town. It seems like kids barely party anymore. As long as they clean up afterwards and don’t break a bunch of stuff, I’d pretend not to notice.
Have you considered letting them party and being a cool responsible adult that sticks around to make sure everyone is safe. I had some friends growing up with parents like this. Their theory was the kids are going to party anyway so if you give them a safe space its less likely to go poorly. Anyone who got a little too sick or emotional ended up with an experienced adult to help them recover.
