Can I ask an owner to pick up their dog if he keeps peeing all over my house?

When accepting the request to watch the dog I was told that their dog was potty pad trained. I have watched other dogs who are potty pad trained and they clearly know to go on their pads. This dog will only poop on the pads but refuses to pee on them. I have been taking him out every 30 minutes to go outside and he will go potty outside but as soon as he gets inside he pees all over my rugs, furniture, floor, etc... It is one thing to have a few accidents but he has peed 10+ times on my furniture/rugs. I do not know what to do. I have picked all my rugs up at this point and now he keeps lifting his leg up and peeing on the side of my couch.

What do I do? He has already completely ruined one of my rugs, I can't get the pee out with pee cleaner or other techniques.