This could be an interesting fight.
The federal courts have ruled the 14th Amendment does not apply to Samoa. Thus, Samoans are denied U.S. citizenship even though born on U.S. Territory and also don’t have the right to vote.
If the 14th Amendment (which covers equal protection) does not cover Samoa, I think there would be an argument the Obergefell decision does not affect Samoa either.
It’s a little depressing knowing that Samoans don’t get citizenship or 14th protection when you also know how many of them are veterans. They are doing something right to have that many men signing up.