I'm somewhat surprised no one has mentioned this "what if?", but what if the NHL allows the St. Louis Blues to move to Saskatoon in 1983?
*Saskatoon probably has a team for about a decade, and becomes the #1 team targeted for relocation in the 1990s, before Quebec and Winnipeg. It is possible the Blues become the team that moves to Denver or Phoenix, while the Nordiques and/or Jets move elsewhere or possibly even stay put.
*It is possible the Saskatoon team isn't particularly successful after a short period of time because players don't want to play in such a small market, so the team moves even earlier than the early to mid-1990s. Perhaps the Blues relocate to one of the markets that received an expansion team in the early 1990s, such as Ottawa, one of the aforementioned relocation markets like Denver, or one of the markets that never received a team but had or built an arena, such as Hamilton, by the late 1980s.
*St. Louis becomes one of the strong candidates for NHL expansion in the early 1990s. It is also possible the Saskatoon team moves back to St. Louis as the first of the Canadian teams to relocate in the 1990s.
*After losing the Blues, St. Louis only has two major league pro teams, the baseball Cardinals and football Cardinals. Perhaps St. Louis does more to keep the football Cardinals in St. Louis, meaning they never move to Phoenix in 1988 and the Rams never move to St. Louis for 21 seasons (1995-2015). The Rams moved to St. Louis because their owner at the time, Georgia Frontiere, was from St. Louis. Perhaps the Rams stay in the Los Angeles area and move back to the LA Coliseum after the Raiders move back to Oakland, or perhaps the Rams end up being the team that fills the void in Baltimore in the 1990s, or the void in Cleveland after the original Browns moved to Baltimore in 1996. Perhaps instead of selecting Charlotte and Jacksonville as expansion cities in the early 1990s, the NFL selects Phoenix instead of either Charlotte or (more likely) Jacksonville as an expansion city at that time.