even if he is in Canada? and refusing to sign, do pcc or medical or allow children to come with their mother to the same country he is in? isn't ircc consider such facts?
It doesn’t sound like you are together with your partner so family reunification doesn’t apply to this situation. It also appears as though your ex-partner is an asylum seeker and may not have permanent status in Canada yet. There isn’t family reunification until a protected person is a PR. As already indicate you need to sort out your custody issues and fight for sole custody.