Agreed the umpire is way too wide. Very rarely should you line up wider than the outside shoulder of a guard. The only reason you follow the ball on a pass is to help with catch/no catch and that doesn't apply here. Once the play goes wide you are focused on blocks inside and behind the runner. There is no reason for you to be focused enough to rule progress or OOB. You should be looking anywhere to know WHEN he stepped out of bounds.
One thing I have helped with on a play like this is the location of the progress if that's what is ruled. For some reason the wing was way off on his spot and didn't get help from the offside wing. He initially marked the player 2 yards behind where he was contacted (I had the benefit of a big line in my peripheral) so I just shared that with the wing. It was up to him if he wanted to use it. That's all you should offer here.
I wouldn't say you never help rule on progress on a play like this, but it should be exceedingly obvious. This definitely isn't that.
Good luck with officiating and thank you for being willing to come here and request feedback. It will help you get better.