Sounds like your husband has a set of golden handcuffs. He’s going to take a step back in the USA in order to move forward to a major job in the USA.
Most of the pilots flying for overseas carriers that have landed jobs with US majors are from the US or at least have had a US track record of employment at some point in their flying career. Of course there might be some outliers (ie friends or family of Chief pilots etc) that go against the grain.