Lost in that botched flyout was earlier in the inning Cam delivering a perfect throw to Dubon on 2nd to tag Kurtz but he didn't catch it cleanly for some reason. It was like he gave up before he attempted to catch it.
Yeah that's the 1st baseman that has to take charge on the play. You never want your pitcher to catch ANY pop up that high in the air. That's not how that works. Ever. Thus the reason Correa is frantically trying to save Walker's butt on the play.