How can one reconcile a husband's obedience by returning to Canada with a mother's responsibility towards her daughter who refuses to live with her father?

A wife must obey her husband by traveling with him wherever he wishes, provided the country and the route are safe, and that the travel is in the company of the husband or a mahram. It is important to note the impermissibility of residing in non-Muslim countries for those who cannot openly practice their religious rituals there.

Regarding the custody of the daughter, the mother's marriage nullifies her right to custody. Custody then transfers to the paternal grandmother (the mother of the mother) unless the father agrees otherwise. The daughter may not be moved to another country without the father's consent and if it is beneficial for the daughter.

Therefore, either the new husband must agree to the wife remaining in her country to care for her daughter, or the first father must agree to his daughter traveling with her mother, all while frequently supplicating and seeking assistance from Allah Almighty.