Right now, I don't care if he needs to go or not. I just take him out every 1.5 hours just for consistency sake. He'll still go.
I am doing outside only training. If the weather is bad, I would lay a pad out on the (sheltered) porch, but it's still outside. It might be mean, but I have a new home. He already made it messy enough! :P
The breeder is also at lost with the crate issue. Sigh. Oh well. Patience is key then...
You've made it much harder for yourself insisting on outside training only... You wouldn't HAVE the messes in your house if he had an "approved" potty spot in the house. Kodi came trained to a litter box, and has had very, very few accidents, even when he was a very small puppy. (and those were our fault for either giving him too much freedom too soon or not noticing his signals) The few times he's needed to vomit, he's even gone and done THAT in the litter box, and no one ever taught him that!
Oh, and yes, they very quickly learn to pee on command... Kodi will always pee if I tell him too, even if he can only squeeze out a drop or two. This is actually pretty useful, especially right before getting in the car for a long car ride.
So just because Roshi DOES pee every 1.5 hours when you take him out doesn't mean that he couldn't have waited longer. But right now, the goal is to establish good habits, which means, as far as possible, never, ever put him in the position of having to pee in an inappropriate place.
Also, remember, it's going to take some time to undo the mistakes of the first few weeks. How long ago did you come on the board and change the way you are handling things? A week or 10 days ago? It's going to take longer than that to re-train past the habits he started to develop before then.