Feet don’t matter. Feet establish if the control was inbounds which thus moves the control to possession, but control is in the hands. The rule talks about control, not feet, not possession (actually it’s deciding who to grant possession to based on control) Jennings had solo control first, if Tate ever had joint control it was after (milliseconds after but still after) Jennings had control.
I looked up the rule and I see it does talk about “control.” You’re still going to find people who say Jennings didn’t have control since Fate’s arm was in there and he couldn’t pull the ball into his chest. Nevertheless I’ve always said it was a Jennings catch. The possession thing was merely the best defense of the call I’ve heard.