I do know that the most important and step would be to end immigration, while fighting with all the delays and obstacles, and holding efforts, that we can.
Ending or drastically reducing immigration needs to happen regardless but I doubt it will change the federal definition of marriage in the short or medium term. Delaying tactics may help in the short and medium term but not in the long term. I don’t see much of a solution in what you’re saying except maybe in the long term. Which means it might make sense to seek short and medium term solutions at the state level, possibly like what Mississippi is considering.