I had a similar situation with Rugan: I had used Disguise Self before I entered the Zhentarim Hideout, but Rugan still recognized me as the person who saved him.
A funny thing I noticed when using Disguise Self is that when you talk to a companion, the dialogue options change, and you can ask questions again that you had already asked in the respective companion scenes - even if you disguised right in front of them. The phrasing of the questions and answers is also slightly different, as if you haven't met before.
Or maybe the memory loss and difficulties to recognize faces are symptoms of our tadpole situation 😄
