Hi!
I just faced the same problem myself… and using your same debugging outputs I also got it was the Engine.Character.ServerMovePacked the one firing an additional time the notify in server.
In my case, don’t ask my why… enabling Root Motion in the Anim Sequence the behaviour dissapeared. But I would also love to understand why exactly this happens and how to avoid it in server without having to use root motion, in my case the animation doesn’t move the character, but in case you want to avoid root motion this is still an issue.
I hope at least it helps you with your situation.
Cheers!