I think, why the President of the US didn’t share that with Xavier, is simpler. As POTUS, if it is revealed that US citizens are still alive in great numbers he would have an obligation to go help them. With the very limited resources of Paradise, that would destroy any order - as small and selfish as it is. If Paradise gets known in the outside world there are many,many more guns, weapons and desperate people who would overwhelm Paradise in short order. A horrible dilemma for anyone with a conscience. This dilemma now falls to Xavier.

The show was poorly written and often made little sense. A reveal of a sith lord and Yoda guest appearance at the end an attempt to salvage something. The actors - good or bad - cannot overcome sloppy writing. I've read the shows writers had to force fit into narrow run time slots created problems, so that contributes to many fans observed disappointment - only made worse by how much money was spent on this debacle. Disney efforts at producing great entertainment continue to slip away.