Because Elliotts has proven everywhere he has gone that he can win. Doesnt matter where he played, he won. He has shown the potential he has, he has shown that he might indeed, one day be a number 1. Id rather give him a shot at less than a million dollars a year than Leclaire and get the exact same result.
Taking on Leclaire at 3.8 mil for mulitple years over Elliott (who has basically proven the same amount at the NHL level, nothing) at less than a million dollars. I'll take the question mark with the least amount of risk and lowest cap hit. Auld IMO is a better goalie than Leclaire right now anyways.
EDIT: On top of that, we lose Vermette... the deal is garbage IMO and has been a rumour that has been put out there for over a year now... not gonna happen.