Check out this screenshot (Heroes 3 + Photoshop).

The screenshot from Docent isn't very appealing...

That's not a screenshot from Docent, but a screenshot from Greymag. :) And Greymag, in turn, downloaded it from the 3DO website.

possibly from 3DO themselves

Not possibly, but definitely. The 3DO website is long gone now, but when it was active, these screenshots were posted there.