I am not quite sure why you didn't ask Airbnb to cancel the booking, when you saw there were many more people arriving at the property then had booked.
What do you mean by 'they replied by saying to will stay within the agreement'. Surely they had already broken the agreement by having all these guests. You couldn't have really believed that they weren't going to stay???
So to minimise further breaking of your house rules. Contact Airbnb tell them that the guest had violated your house rules by having many more people book than had paid (even though they had assured you this would bethe case), presenting a security risk to your property by leaving all the doors open,and putting your furnance at risk by having the temperature too high.
Ask them to cancel the booking straight away so you can ask your guests to leave.