Considering the Josephine chick flat out said that she has zero romantic interest in Phil, lives far away (although in the US), and is married, I don't think she's a catfish or tryna smash. I mean, if she is trying to catfish him, she sure is playing hard to get.
Also, I've never actually paid attention to Phil's Twitter until now, and... jesus christ. The trolls on Youtube can be bad, but they're mostly just shitcommenting. The trolls on Twitter are fucking nuts, though. They're basically harassing this chick, picking out the weirdest, smallest things as evidence that she's someone else pretending to be her. She probably doesn't care all that much about "proving her identity", and why would she?
And there's just a bunch of dumbass over-the-top personal attacks against Phil that don't help anyone but him. Phil is a sketchy scumbag with plenty of actual shit to assblast him over. When they call him a "gouty pussy manbaby whose gf left him" with zero context for that vitriol, that just makes him look like the poor, innocent victim of angry, psychotic trolls.