The current UND HC has the final say about whether any of his players get to play in Davos. Not having enough D to field a full line-up levels the ice when it would otherwise be fully tilted in UND's favor. Plus it's a given that bottom-dwellers like Mercyhurst play their best games of the season when playing UND. See RMU, Bemidji, Clarkson, Canisius, etc.
Nightingale did the opposite & determined that his team's NPI standing was more valuable than any foreign cultural experience for his players. And that should be the lens a HC uses when making roster decisions. PSU has 4 players in the SC, but they conveniently play Sat-Sun that weekend.
Others have said that it probably won't matter because it's Mercyhurst, and they're probably right, but it does open the door a little wider for an upset to occur. Losing a close game against them would make UND's NPI dive faster than a whore in Amsterdam. And that would be an unmitigated disaster for the season in terms of seeding.