Resolving a guest's dispute

Our BnB is pet-friendly.  Without notice, our guest showed up with 3 German Shepherds for a two-day reservation.  After they left them in the room for a period of time (duration is in dispute), we asked them not to leave the dogs in the room unaccompanied because other guests complained about the loud barking.  The guests chose to leave during the night and are refusing to pay for the second night.  We are suggesting that we together submit our statements to a third-party for evaluation and a recommended settlement.  Would anyone be willing to review and recommend a resolution? If not, can someone suggest an independent party we could turn to? 

Louise Carey 9 months ago

I have a problem with a guest who damaged the bathroom and have not been reimbursed.  Is there any dispute resolution on booking.com to resolve this?