They definitely can host their own servers through WSL / their own dedicated servers, independently from AWS. No way they only develop the game through connecting to AWS instances, that would be way too expensive with the amount of people they have working on this.
Licensing and agreements could be a problem, but that immediately would stop being a problem if people decided to boycott the game en mass, unless there is a server browser and dedicated servers, because money speaks at the end of the day. Unfortunately someone at EA or Dice decided that SBMM and no server browser is the way to go and they gaslighted everyone else into believing that that portal server browser is the same.