I didn't mean that that line is a remnant from earlier development, but rather, that it seems to be his only acknowledgement of having done something wrong to the Gur other than kidnapping their children under Cazador's orders. I still think the current game heavily implies he did something very bigoted to the Gur when he was alive, it's just dropped and never acknowledged again.
I also don't know for a fact that Maiden Fel was a hag- I probably considered it, but I don't think we had proof back then to conclude that. All we know is that dead Gandrel described her as "Reason even monsters have nightmares" "Dread creature, but not the one I hunt" and as a "Wise woman with questions". The fact that she wants Astarion unblemished reinforced my idea at the time that she had business with him, from way back when.
Interesting. That hint remains. The fact that Astarion was a magistrate in any case makes it seem like the Gurs attacked him (before he was captured by Cazador) because of his judicial activities. But, on first playthrough, due to the lack of explanation, I was under the impression that the Gurs were more like such nomadic bandits and attacked him as a representative of the law, or just an overly rich guy who wandered into the wrong neighborhood. That's basically what I thought until I was told his story from the artbook.
About the hag - it was written about in that VK post you cited earlier. It coincides with the letter from “M” (Maiden Fel, maybe), she called Ethel her sister in the letter. When I read the VK post I immediately thought of the very strong appearance resemblance between Ulma and Ethel - they really do look like sisters, one face. Even when I was playing and didn't know any of this, the first time I met Ulma in the city (she behaves rather harshly with Astarion, the reasons are clear, my attitude is subjective, but still) I thought something like: “That old hag!”
. And then I started thinking about where I saw her - and remembered Ethel, thought it was funny, two hags (a real one and in my subjective opinion :)) - one NPS model. Looks like the developers really did use the same face model for them. Yes, it happens, I've occasionally encountered my Tav's “sisters” in the game, but after reading that post it all came together. “Circumstantial evidence” matches, plus the night hag in DnD does give nightmares. But from what Gandrel said, the Gur knew who she was, so the option of her deceiving them can definitely be ruled out.
