Hate to be the bearer of bad news, but this is a classic case of many beginner's hosting mistakes.
1. You are fairly 'new', the hustlers pounce on such places: new / inexpensive / long stay.
2. You offered your most lovely place (may I add), for a $105 total price for 3 bedrooms / 6 people. That is $17.50 per person per night. At that price you are fortunate 'The Misfits' only brought 6.
3. Third strike - allow them to stay for 30 days (i.e. risk) without any clue what was going on till they left. Thank God they did leave (i.e. the possible danger of a 30-day stay meaning squatting, a whole other subject).
Of course, this begs the obvious questions from the peanut gallery (us old beat-up timers here) -
~What were their reviews like? I see that they have not left any, little wonder since they are probably busy packing quickly and leaving town.
~Did you assume the presence of Aircover would cover you no matter what happens (which is the program's inherent pitfall). Too often serves for beginning hosts not to be cautious enough.
~Where the 'emotional support animals' legit, or just sheer nonsense (i.e. free pet boarding)?
I suggest you do the best you can under these very unfair circumstances. Do not feel like you are alone in your approach or outcome, we all been there at least in part - in the beginning.
No, Aircover is not a scam per se, it may be full of good intentions, it's just gives the wrong impression and it is very hard to implement consistently and fairly.
Good luck, you and your lovely place deserve it. @Sonja482