I asked in the match thread. The ball went straight back to the shot location too, so the foul-rebound comes into play, similar to the Nketiah incident.
It's completely inconsistent refereeing. The precedents and ambiguity mean they can pick and choose how they want laws to apply. There's so much room for manoeuvre for the refs, especially on things that are fouls but are never typically given. They make a choice rather than having an obligation by the rules, and it feels for a while like we've been far down the negative tail of the decision distribution. It's easy to give a decision against United.
I'm in favour of the ref being king (preferably with better training) and accepting their flaws, but now we've got the worst of both worlds - shit refs and shit VAR ruining the game.