mm77,
A lot of the DIII coaches, in fact, have not even started serious or intense recruiting efforts. While the lack of response to your evaluation might mean something it terms of DI, which are heavily into their recruiting framework, it may mean nothing in terms of DIII.
I agree with Homerun04, if you can identify the schools that were present, start calling them and emailing, especially at the DIII level. The velocity topping out at 84mph is acceptable to generate interest at many DIII programs.
Good luck to you and keep us posted on how things are progressing. If you really want to pitch in college, and it sounds like you do, you may need to be persistent in calling and contacting coaches to generate some initial interest. If you want to play college ball enough, then it is worth all the effort to pursue that goal.