I really wonder if there is any document left by the german pilot , telling the story from his side.
If there is, no one has found any personal comments or even official records.
I was curious myself so I did a little research and it turns out that there is quite a bit of evidence in the historical record to indicate that Ergon Mayer wasn't the German pilot. That claim can be attributed to Barret Tillman and later repeated by Freeman in the "Mighty Eighth" that claimed Ergon Mayer gave a radio interview during the war in which he claimed to have shot down 3 P-47s, including one with the markings "P HV" (Johnson's P-47). However, there is no record of such interview nor did Mayer file any kill claims on that day and he was reported to have been in Brittany with his squadron.
There are records for 3 German pilots that put claims for P-47s that occurred in the area Johnson described in his own account. According to Johnson, he was attacked near Dieppe, over the English Channel. One of the German pilots, Lt. Waldemar Radener put a claim in for a P-47 after he saw it go into a spin after hitting it and another German pilot, Wilhelm Mayer, put in another claim for a P-47 in that area but had to settle for an unconfirmed as there was no other German witnesses. Mayer's claim also meshes with Johnson's account in which he stated the last attacker was a single FW 190. The third German pilot that put a claim for a P-47 in that area was Wilhelm-F. Galland, but it most likely was another 56th P-47 he shot down as Galland also put in another claim for a P-47 near Neufchâtel-en-Bray.
I guess we'll never know the other side of the story.
ack-ack