HELP! Guests having a party in my house RIGHT NOW…

Lala I want to completely be in your side but… I think there is your " fault" here present. If they live few suburbs away what reason did you think they rented your place?
I had locals renting from me once that were obviously young and I had a whole conversation with them about noise and crazy neighbor.
Your guests did not damage anything, they did not make any noise after 10 pm. Their noise was significant to neighbors but not against the law.
I think if you had in your rules " not registered guests are not permitted in apartment" then it would make the whole thing bad and it would mean they broke the riles