I think the must win faction is moreso to have any hope of fighting for home ice in the first round or at minimum avoiding the wild card spot that crosses over.
Nashville has a maximum of 109 points but looking at the records of their opposition and their past performance against the various tiers of teams their expected points in the final stretch is about 21 points putting them at 94 points. Edmonton would need to go 7-8 in the final 15 to match that 94 points, so Nashville needs to be pretty hot down the stretch to catch Edmonton if Edmonton is putting points away.
As for Calgary, their maximum is only 103, and expected is somewhere between 89-92. 6-9 gets Edmonton to 92 points. So it would take a miracle from Calgary or complete implosion by Edmonton for that to happen.