I'm babysitting a dog that doesn't want to go out at bedtime. Any other time she's fine. I finally decided to take her out on a leash and stay with her in one spot until she peed. She's very strong so I had to put her on a wire tied to a post to keep from being dragged back into the house. I stay just out of reach and as soon as she's finished, I let her loose. After 5 days or so, she's getting the picture.

I don't know if that's any help.

It sounds like he needs to understand that nothing in life is free. Have you tried this method?