Before me and my wife got married, we're already in a relationship(not living together) for 6 year before she migrate. Then after four years, she flew back and we got married. Shes not able to make a visit during those four years. Is it a red flag?
If you didn't see each other for 4 years before marrying, that is a massive red flag. People in genuine relationship make every effort to see each other. I would say you have a very high chance of refusal.