Continuing on the Montreal discussion, there is a new sports complex being built in Laval, which I think would be an appealing venue as a possible Worlds host. Place Bell is scheduled to open this fall, and has a seating capacity of 10,000 (which meets the requirement outlined in the Skate Canada proposal). According to the Place Bell website, in addition to the main rink, there are 2 practice rinks on site as part of the complex (one ice surface is NHL sized, the other ice surface is Olympic sized), so that would solve practices. You have international airport access close by, lots of hotel rooms in downtown Montreal, and the complex is adjacent to a metro stop, so it's easily accessible for fans. I'm assuming that since it would be a relatively new building by the time March 2020 rolled around (2.5 years old), it would meet whatever technical specifications are required. Assuming there is flexibility there for the Laval Rocket to play their hockey games on the road for 10 days-2 weeks, it could definitely be a place to consider.
https://placebell.ca/en
https://placebell.ca/en