I think that if the memory-wipe only obscured the Warriors' faces and nothing else, then people would have made memorials with their names or, on a meta level, it would have been mentioned in the introduction. It's more likely that the spell made people forget about their individual features. They know the Warriors existed, but can't tell anything specific about them.
We'll have to wait until we play through the storyline to know all the details, I guess.
We'll have to wait until we play through the storyline to know all the details, I guess.