The problem is not that there is possible constraints to Joubert's training, but the fact that he doesn't accept any solution proposed to him.
For the rink in Poitier : he knew in advance that the rink would close, so he had to know that a back up solution would be needed. Either he could organise something with Guyon, or leave to some other place. He didn't organise anything with Guyon, he didn't anticipate a move to whatever place. So eventually he was asked to come to Paris to train in the national centers. He didn't like it and left. He was offered to skate abroad, he refused. What can be done for someone who doesn't seem to adapt to anything that is possible for him ? Apparently he wants to train with Guyon only. In that case he should have organised that option in advance.
As for the training in the USA, it might have not been the right solution for some skaters, but it happened to be the right solution for many other skaters. Options may work for some people and dysfonction for others, this is life and that doesn't mean that no one should try just because it happened not to be perfect for some people. All the big names in figure skating had to make a move or some sacrifices at some point in their career, this is part of the high level training, going where the experts are and try options that are not comfortable for what is usually a short period in a lifetime.