They get the edge but it's not as drastic as you may think it to be. Statistically speaking net punting, punt return, kick return, and kick return defense are essentially a wash with JMU holding a tiny lead in all of those categories.
The only place I think there's a significant advantage is when it comes to clutch FG kicking... I think Crosa is passable but I don't trust him (or the long snapper/holder) if it comes down to needing a FG in crunch time. Rathke is a senior who has made some monster kicks in the past (like his 46 yarder in the Fargodome to break the tie in the 2016 semis and his kick to beat Weber St in the 2017 quarters) but his range is limited (as is Crosa's). I hope Entz has the same testicular fortitude he had late in the 4th quarter in Brookings on 4th downs in this game. The Bison offense is so good that if it's anything inside of 4th and 4 and outside of a 40 yard FG I think the offense has a better chance at converting a first down than Crosa does a FG.