There is another story like this where the German ace Egon Mayer escorted a shot up P47 flown by Robert S. Johnson back to the channel after being unable to shoot it down (he was out of cannon ammo IIRC).
Johnson became an ace himself later.
"Mytsicpuma" made a very nice Il2 movie about it:
Not my time to die
354MB
Definitely worth watching.
