I’m watching the exact same replays that you are, and it was not an indisputable call. Viewers tend to see what they want to see. I hate the Chiefs. But I couldn’t have reversed that call based on that replay.
The LJ at bottom has NO SIGHT OF ball. Allen's back was to HIM.
The ball was in his left arm, not right arm l.
Meaning if his body was over line, so was ball.
That is what the top LJ saw. But for whatever reason, deferred to the bottom LJ who had no idea where the ball was.