So based on this it was pretty much expected that the evil ending for a Chosen Dark Urge will most likely not even have an epilogue showing any aftermath and will just be a very short straight-to-the-point "Yay congratulations, you're EVIL! Look at your awesome Durge having their little evil moment with an evil punchline... quickly lets fade to black!" type of ending.
If you want to hear something even more disappointing, that ending is not even unique to Chosen Durge. Chosen TAV gets the same exact ending. Only difference is Tav says "In Their Name". It's honestly kidna depressing that's all we get on Chosen Durge when it's spelled out exactly what the durge ending is.
Something even close to what you suggested would be much better than what we got, and I hope Larian is redoing this ending for Durge at some point.
I get it, not many people fully commit to doing Father's work, but for those of us that do, it'd be nice if we got the ending we were actually promised.