I'm still amazed that Ime bothered to use the challenge with 3 seconds left to switch a foul from Rob to J Rich when Rob wasn't even in foul trouble.
In my understanding, you don't challenge a call to go from x to y. You challenge the call in general. Refs decide what happens next.
So in short; maybe we went "that wasn't a foul" and then the refs were like, "you're right, it wasn't, but that JRich stuff was".