US Immigration from Uganda

My LPR husband is still stuck in his country. It has now been 9 months. We are hopeful for a flight next month, but it isn't guaranteed to happen.

I'm very worried that even once he gets a flight back, he might get problems in the airport. Every time he has returned before, they have taken him for questioning.

Myself and our two babies travelled there with him in November 2019, and returned in February, but he remained behind to see our trade school through the end of their term. Well, everything got shut down before that was possible.

We do have his return flight info for the flight that he was supposed to come back with before the airport shut down. He also still has insurance, driver's license, a bank account. We don't have a lease together because we live with my parents.

What is the likelihood of him being denied entry at the airport? Is there anything we can do to prevent denial? If he is denied, what happens? Will he be detained or allowed to come home to wait for a hearing or what?