There is however a part where we see an Apirant about to ascend, likely not having had his memories removed yet fall nad be turned into a Forsworn with wings.
Not to mention, if removing their memories is required to get their wings then why would any of them have wings at all with thsi line of thought? Their stated reason for being is not wanting to remove their memories.
I suppose it is possible that their memories are removed right before the ritual where they become ascended and that is where they get wings, but that just seems a pretty rounadabout way to explain why only Ascended Kyrians are supposed to have wings and yet Forsworn are failed Kyrians who additionally have wings.
Still though, my main problem is not really getting where Ersula is seeing Ascended Uther joining the Forsworn. From where i am standing it still seems more likely that his uncorrupted model is meant to show up later in the Kyrian Covenant questline. Thye do afterall specifically mention it being possible to reverse the process of becoming a Forsworn.