So I didn't remember the pop up play. I went and watched it and checked the comments for a post of the rule. I would argue part that makes it not an infield fly is the part where it says it's the umpires judgement and should be ruled immediately. On one of the replays you can see the left field umpire, who I'm assuming makes the call, and he doesn't left his arm to, I'm assuming, signal the fly rule until just before the ball hits the ground. So to me, letter of the rule, since he wasn't sure right away if the infielder could get there, and was holding judgement till the play developes further, that makes it a bad call.