I can hopefully help give you some answers. I coach in Divison 1 (NCAA bubble team) and sorry to break it to you, but full rides are almost non-existent in our sport. We are limited in scholarship amount. It would be crazy to think that we would give a full ride to anyone as we would be seriously hurting the rest of our team having money locked up like that. The only instance I could think of spending that money would be on a sprinter/hurdler who can help carry the team with bringing in a lot of points. Distance runners just don't have as much point potential. They are very important to winning championships, but not the most important.
A 9:15 guy would not get much money at power 5 schools. You would be better trying to get large money at a smaller school, as you would be more immediate impact, thus worth the price for them. Even then, some won't give you scholarship.
If you ever hear someone getting a full ride they are:
1. Lying
2. Their scholarship combines with financial aid to "technically" pay for everything, but that isn't actually athletics paying for everything
3. The coach doesn't tell them the truth about #2 and makes them believe they are on full ride (happens A LOT)
4. They got lucky and I feel bad for the coach, they made a mistake unless they are the next Cheserek.
I ran 13:43 in college, and I was on books. I have a friend who ran 1:49/3:39:13:58 at a power 5 and got books and 25% of tuition. We have a sub 9:20 guy coming in next year who is walking on to my team. No money for him, needs to be faster. Scholarship is tough man. Times have changed and people have gotten faster. Sorry, that's just how it is.
With that being said, you can definitely get a chunk of your tuition covered at mid-majors. For power 5, you have to try the low-tier schools in them. Even then they want game changers who will propel them to compete with the big dogs. They don't want minor improvements.