I will start by saying I don't know how the D1 and D2 courses compare, but looking at the results of each race, Adams State (D2 champs) looked like they would have placed quite well at D1 nationals:
6 Mecheso OK State 29:14.8
9 Farrell OK State 29:26.3
18 Kipchirchir OK State 29:43.0
24 Manilafasha OK State 29:48.5
53 Moskowitz OK State 30:22.5
2 Kevin Batt SO Adams State 29:12.1
3 Tabor Stevens SO Adams State 29:12.2
4 Matthew Daniels SO Adams State 29:16.2
12 David Sanchez SR Adams State 29:49.6
15 John Luterbach SO Adams State 29:57.0
I don't necessarily think Adams State would have won the D1 meet (like I said, I don't have any idea of how the courses compare). HOWEVER, it is definitely a solid performance, and I think they would at least be in the mix.