Dogs are not humans and don't think in the terms that we do. I guarantee his thought process is not that advanced..dogs are in the "now".Maybe he just thinks that if he pees that he wont have to go in his cage?
If he is having accidents, he is not truly housetrained, and is being allowed too much freedom. Or, the training has just not been all that consistent and he's learned that while he should go outside most of the time, it's OK to go in the house some of the time because he's gotten away with it. Considering your other dog is also doing this, I would have to say it's a training issue. You need to go back to basics...no freedom in the house unless he is attached to you and you can watch his very move...as soon as he starts to go, a big NO and immediately outside..lots of praise for an outside potty. When you can't watch him, he needs to be in the yard, or crated. Some dogs just feel that it's OK to go in thier crates..nasty, I know, but if they have done it enough, they don't care...it all takes time.
This sounds like it could be a submissive thing. Does your fiance' or yourself ever yell at him when you have found an accident or do you use the crate as punishment? Dogs (especially young dogs) will urinate to show thier submissiveness. It is extremely important that you never use the crate as punishment. If this happens, the dogs can resent being in there and will be stressed..this can lead to urinating and defacating inthe crate as well. It is also important never to scold your dog for an accident unless you catch them in the act..it is pointless after the fact as the dog will have no idea what it is being punished for.My fiance mentioned to me today that he went to put rocky in his cage and he began to pee all over