This. And it wouldn't be the first time Bioware has recast someone aka Mordin Solus.
It's not like Cook was a celebrity voice actor. No offense to her but she doesn't quite have the status of Martin Sheen or Freddie Prince Jr or Yvonne Strahovski. She's one voice actor in a game of dozens of them in what is I think the game with the most lines of dialog recorded. Even Arkham series replaced Arleen Sorkin who the damn character was made for/based on and had been voicing her for over a decade.
Jaesas issue comes from the fact that she's basically two different characters and how to solve which one gets used since it's all on the players choice. She'll probably end up being a side mission (not quite as bland as an Alliance alert it not a Chapter focused character) as a class (warrior) exclusive companion. Same with Khem Val, maybe Risha, Temple, Tharan...