After reading your post about being in jail, I’m tempted to say you should get out of Japan as soon as you reasonably can. They would struggle to do that to you if you were in Canada.
However, I know that will have financial implications, let alone further separate you from Nozomi and your son.
Heartbreaking whatever you do. I worry, though, that a Japanese legal representative won’t truly be on your side. Conversely a Canadian one probably won’t get far up against your ex-wife’s native nous.
Things have to get better and I hope that something will turn up that shows you the direction you should take.