When the season was interrupted, here were the playoffs odds for each team:
http://www.sportsclubstats.com/NHL.html
Chicago had a 2.6% chance and Montreal was 0.0%.
One problem with using the standings from that point, is that the schedules were not fully balanced. There would have been differences in home/road contests and in strength of schedules remaining. Teams that had a hard remaining schedule benefit, and those that had an easier set of games left lose that benefit. So, the seedings are potentially out of focus, which could result in unfair match-ups.