As for whether Poch will move or not, that is a difficult matter. I find the arrogance of some Man Utd fans, who talk as if Poch has already accepted the job funny but not altogether that surprising. In a similar vein, I do not agree with Spurs fans who say with 100% certainty that he will be staying. We just don't know.
The reality is that the media reports are almost certainly 100% bs if they reference what Levy or Poch are thinking. Levy is never going to be leaking his personal thoughts to some two bit reporter and Poch firstly does not have an agent and secondly is not and has never been the kind of manager to play out his battles via carefully placed stories in the media.
I'm sure Poch will be tempted. Man Utd is a huge club and he'll have huge resources. Reputation wise, at least initially, he will feel he has reached the top in terms of the clubs he can manage.
On the flip side, he has built something great at Spurs and he has a huge level of control here. It would take ages to enforce his policy at Man Utd and, unlike at Spurs, where Levy let Poch get rid of some troublesome players at the beginning (and backed him when he benched Toby for almost all of last season), I can't imagine Woodward being too happy if Poch decides he doesn't like Pogba's attitude for instance and wants him gone. He'll be under new levels of scrutiny and he'll see a club that, for all its fans platitudes about being a patient club, has fired its last 3 managers (in 5 seasons) and seen all three of their reputations significantly worse than when they started the job. And I think Poch seems genuinely happy here at Spurs.
So we'll see. I obviously hope he stays and builds a dynasty here. But if he goes, I'll wish him all the best for what he's done with us, even if it will be a bit galling to see him on the touchline of another English club.