Like Red Devil said, Neal O'Connor includes Doerr in the section on fighter pilots who didn't receive the PlM because the war ended too soon. That is correct, since the PlM took longer at the end of the war to be approved, at least two months and regular/active officers were favoured above reserve officers so the latter ones could get them after over two months! Doerr was a GMMC winner and afterwards promoted to officer rank (sometime after his 20th victory, don't know his exact score at the time) and was instantly eligible for the PlM but it would take longer for him than for others and he just didn't make it.
I have never seen any pictures of Doerr with a PlM and in fact I have only seen one such picture where a non-PlM knight actually wore one: Hermann Frommherz (29 to 33 according to various sources) who tried to obtain a PlM from Prussia as late as 1929! Without the Kaiser's signature, there would be no PlM awards and Carl Degelow was thus the last man to be granted a PlM on 9 Nov 1918. If Doerr wore a PlM after the war, I'd like to see a picture of that. I have a photo of Werner Preusss with a PlM touched in by the photographer, did Preuss wear a PlM after the war?
Did anybody else?
To return to your question Soderbaum, Doerr didn't receive it in 1919. No possible way.
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