Well, when we had a baby, our Maine Coon cat began marking. We did the vet check (which you should make sure there are no stones, infection etc).. nothing. We put on prozac… didn't help. He pooped on anything of hers he could find. After 5 mos our friends came over and took him back home with them (he lived with them for 3 mos when we were moving, then 6 mos when we lived there looking to buy our house).
We would have coped simply by keeping her stuff up and hoping he got over it, but he was a very unhappy camper. New home, no one playing with him 3 hours every night like they did... it was the right decision though my husband mourned for years that his "son" abandoned him.
My only advice is to get him totally vetted, and then make sure he gets tons of attention, and to get good enzyme cleaners to totally remove the odors. Your cat, unlike ours, is young. I think you have good chance of it being okay.
But why is Cambria peeing in bathroom floor?