Assuming he went straight to Juco out of HS and competed two years with no lengthy breaks, I don't think he'll find much difficulty from an athletic regulation/qualification standpoint - others can speak to this in more detail (although I do believe there are timing elements with regard to contacting other schools). However, I would suggest he also open up his target scope to include NAIA schools. I say this for a few reasons...
- a majority of D3 schools are less inclined to look to Juco transfers, while quite a few NAIA's thrive on bringing them in (yes, there are several exceptions to both).
- NAIA has athletic scholarship $. D3 does not.
-NAIA regulations are bit more loose with transfers than NCAA.
-Generally, the range of competition is similar to D3, so he will be fishing in a similar pond.
Also, the bigger concern, regardless of level, will be whether his JC classes transfer and how many. This varies from school to school. Many JC's have preferred partner schools but this is usually tied to the nearest state schools.