Let them go.
First of all, they are in the top 5% of wage-earners in Canada.
Secondly, there are plenty of young doctors waiting for secure and guaranteed  jobs in Canada.
I know of several doctors here in Quebec who max out their pay week in 2 days, then travel to Ontario and the USA for even more money. Let Ontario ( and Quebec) doctors do the same if they want the extra cash, or leave!
I also know dermatologists making thousand each and every day, and of a GP seeing 100 patients a day, and making a million plus a year.
If jot's money doctors want let them learn from those doctors making the big bucks!