Hi. My puppy used to be the same way. He would pee in corners and where I can't see him, so try as I might I couldn't get him potty-trained because he didn't want to go in front of me.
What I did was: I did newspaper training, where I put a few newspapers in every room. But with his reluctance to peeing in front of me, he didn't use them. I started congratulating him when he peed. Anywhere. And I started using the word pee-pee when he was doing it. Now he no longer hides it, he actually does it in full sight and this in one week
. And usually on a newspaper. He is only 3 months old, so I am taking it slow. Once he was comfortable to pee in front of me I took him outside and told him to pee-pee. He doesn't do it on command yet, but he does do it in the 15 minutes we are outside. I leave the security gate on the door (he can fit through) and now he goes outside on his own. He still has accidents, but things are going much better than about a week before.