Congrats on finding your paternal gr-grandad. That is wonderful news. And much success with finding info re: your maternal gr-granddad and Bishop College. Hopefully, someone will have some further suggestions for your search and will post.

My most directed research experience w/HBCUs has been with non-academic records. I contacted Tuskegee when seeking info about a relative who was lynched in 1895 as Tuskegee houses such records. I contacted Claflin when looking for my gr-gr-gr grandfather's obit amongst Methodist records. Claflin is Methodist affiliated and houses Black Methodist records.

Lastly, I also have had success with the Meharry directories. Thank you Tenaya for posting them. Town lore is that the first black doctor of Colleton County, SC attended Meharry (no biological relation to me that I know of). Indeed, I find the name in the directory (!)--but still have not found any information to confirm that he was the first black doc. I have a long list of places that I contacted to try to confirm this, but no luck yet.