@Laura2592 I spoke with my insurance broker the other day, and mentioned your predicament. He said that you should have an attorney (or your insurance company) provide you with a disclaimer letter that you can send via the platform (tracking/proof) to any future non-abiding guest, advising them that as they have flouted the house rules, they will not be covered in the event of an accident, and you will be held harmless and may not be sued in the case of such an event. It doesn't stop them from being stupid or careless, but you can protect yourself from their actions.
I provide my guests with a detailed rental agreement that has protective language in it for my liability in the event of accident or misuse. Under the NC State law, providing payment for the premises implies consent, no signature required, as long as I have proof that the contract was delivered to the guest; so the door access code is in the contract! I have not researched to see if Maryland has similar contractual language -- speak to your attorney!