The 8th stage of the annual John Van Caneghem Tournament (2007).

Is it also possible to break through the Gate with Arch Devils without Gorgons and Wyverns ??

Well, someone else would definitely have been found to replace them ;)

Added after 5 minutes

I only sent it to VDV - I hope there won't be any issues with receiving it.

Well, I think there shouldn't be any issues. Even if we account for the fact that the save wasn't received for some reason, I think it's no longer that important, since I've already put some things on public display ;)
If anything - this is a "Dragon Fly Hive" as evidence in your favor.