He didn't need to jump, all he had to do was continue to run the route. Ball would have landed at the 50 or 49 of the Packers, he makes a high point of contact at the 47 and starts his jump with the Ball still 4 yards from him. Cant tell me he couldn't have ran an extra 2-3 yards and caught the ball in stride.
Sometimes these receivers tend to make the catch harder than it has to be. in this case I truly believe he did just that.