How to deal with a runaway?

So I’ve been boarding for several years now and I’ve had my first runaway. One dog is a 80 pound Great Pyrenees and other is a German Shepherd/Lab mix. Stupid me didn’t do a meet and greet and it has been a total nightmare. I had a bad feeling when the owner finally got them into my apartment and the Pyrenees just hicked his leg up in front of us and pissed on my couch after JUST walking him. The owner response to this “you might want to move that he thinks it’s a bush” (my throw cover). Wtf? Red flag! Then he advises he forgot their food and could Venmo me the money but I told him we could deal with that later. Fast forward to an hr later. I was coming in the house and checked before opening the door to make sure no was at the steps. Well these dogs were hiding behind the door and just bolted across the complex. What a nightmare! I immediately called him and told him what happened, grabbed my car keys, and their leash. Drove around the area for 30 mins. No sign of them so I made several post on FB and alerted the cops/animal control. 5 hours later I get a call from the owner saying someone found them. They were still in the complex soaking wet and muddy so I had to lay all of my spare comforters down on the floor so they wouldn’t track mud on the carpet. He lied in his profile and said they were chipped and got along with other dogs. A complete LIE. I’ve had to cancel two overnight bookings because they are not friendly towards other dogs. Thankfully everyone was completely understanding and appreciated my honesty. They do not listen to any commands barely their name either. Has anyone experienced this and how did you deal with it?