You're attempting to apply rules that don't apply to this situation. This isn't a rebound. This isn't guarding. This is a player attempting a shot. The player with the ball gains his position without contacting any other player illegally.
The original post? If the defender doesn't jump within his vertical plane, then it's a foul on the defender.
4-23-3c
After the initial legal guarding position is obtained:
The guard may move laterally or obliquely to maintain position,
provided it is not toward the opponent when contact occurs.
The rule does not exclude an airborne defender. If he moves, leaps, jumps, runs toward the offensive player and creates illegal contact, he has fouled. Why do you think defenders are coached to never leave their feet?
If the defender stays within his vertical plane, the foul would be on the shooter.
4-45 -1 through 5
Verticality applies to a legal position. Following are the basic components of the principle of verticality:
Legal guarding position must be obtained initially and movement thereafter must be legal.
From this position, the defender may rise or jump vertically and occupy the space within his/her vertical plane.
The hands and arms of the defender may be raised within his/her vertical plane while on the floor or in the air.
The defender should not be penalized for leaving the floor vertically or having his/her hands and arms extended within his/her vertical plane.
The offensive player whether on the floor or airborne, may not “clear out” or cause contact within the defender's vertical plane which is a foul.
From the original post, I don't believe this defender stayed within his vertical plane.