Is that Takakazu Abe from Kusomiso Technique holding the flag? And if so, is this really the only image on Danbooru in which he properly appears (as opposed to his famous face being pasted on someone/thing else)? I did a tag search, and while both tags exist, they're listed as having 0 images.
Considering the fact that the previous Gag Comic Goudou cover had each artist represented on it via notes, I tried my best to do the same here.
While the pixiv source includes a now-dead link to Rodney's now-gone Livedoor blog, the Wayback Machine has saved a copy, giving us what artists are involved. Hopefully everyone's correct.