This is probably why. - tldr; "retail Authentic" jerseys are made in Indonesia. Adidas (or more specifically, their factory in Indonesia) doesn't make them in goalie cut. Would be willing to bet Fanatics will not either, there is no money in producing goalie cuts for the general public.
True NHL game jerseys are made in Quebec (source).
It sounds to me like this shop in Quebec ghosts for whoever has the NHL jersey deal at the time (Reebok/Adidas/now Fanatics).
A quick Google search yields SP Apparel as a jersey manufacturing facility in St-Hyacinthe, and their blurb says they contract with Adidas and Fanatics.
Their catalog claims all 32 NHL teams are in their product:
So I guess order an SP Apparel jersey if you want the closest thing you can get to the real deal.