Found a really good source including a picture of the first edition. It looks like that they were mentioned indeed in the 2nd edition to be more dog like in a sense of voice “yappin like a dog” and smelling like damp dog. Their visuals however were not really dog like. So I assume it was maybe both a mistranlation and an over interpretation of some texts from 2nd edition or just pure free choice from the author of this anime. https://www.belloflostsouls.net/2022/01/dd-monster-spotlight-kobolds.html
I guess with some imagination you could say the muzzle does indeed look dog like but the rest? I mean even if you morph some reptiles into humans you’d get such kind of muzzle. It’s not really that “distict” imo, but I get why some would say otherwise.
“Kobolds were first described as hairless humanoids with small horns by Gygax in the Monster Manual (1977)”
https://en.wikipedia.org/wiki/Kobold_(Dungeons_%26_Dragons)?wprov=sfla1