I think that's IV gruppe and I'd do it red.You can just see part of the "squiggle" here and it looks the same as the red number.
I'd do the victory markings red too for the same reason.
Interpreting B+W images is very subjective and I claim no particular expertise,ultimately it's up to you!
Cheers
Steve
..Styling correct ?...don't make me laugh...the guy is a menace...does no research whatsoever that I can see. I once bothered to email him with a bunch of corrections for his Luftwaffe a/c profile 'artwork' . Got a very unpleasant mail back. Which is why whenever I see his name mentioned now, I can't help but think 'idiot!'