Hello everyone!
We'll I consulted with an dog behaviorist friend of mine who consulted with a dozen different trainers around the country that she has worked with.
They sent me lots of ideas, some of which won't work. One of the things someone suggested was more exercise. However he's a 5mo old newfie puppy so there is only so much one can do. That combined with the sheer heat of Arizona (already in the 90's here.) it really limits the amount we can do outside.
The two suggestions that I felt might work are a combination of things.
One: Go back to going outside with him on "potty" trips and praise the heck out of him, giving him a treat when he does his business.
Two: If he messes in his crate, drag him out and put him immediately into another crate while his is being cleaned. Then he doesn't get the reward of coming out of his crate or going outside.
Hoping he'll get the idea that pottying outside means praise and goodies and pottying inside gets him no where and makes Mom mad.