It's tempting to see a connection, but there's little evidence for it. While both, as you mention, may share distant ancestry in the oral traditions of West African --the famous poetic histories of the griots, performed with the accompaniment of drums --they are otherwise unrelated branches of the same tree. The talking blues traces most directly to Chris Bouchillon, a white country musician and comedian who is said to have innovated the style because he couldn't sing. Many of his lyrics, however, were borrowed/stolen directly from the Black folk music of the time. From there the style was adopted by Guthrie, and then Dylan.
The young hip-hop pioneers of the early 80s weren't, by in large, listening to Dylan, however, and certainly not his deeper cuts like "Subterranean Homesick Blues." Instead, they were taking inspiration from the Jamaican tradition of "toasting" over a beat, novelty records like Black comedian Pigmeat Markham's "Here Comes The Judge," and Black spoken word artists like the Last Poets and Gil Scott-Heron. (While Scott-Heron was often compared to Dylan, and was certainly aware of his work, he explicitly denied any direct influence.)
To put it another way, there's a long line of Black spoken-word with musical accompaniment that predates the talking blues lineage, and doesn't have any traceable debts to it. For that reason, there's no reason to look to the talking blues as anything more than an incidental predecessor to rap. If they have a familial resemblance, it's most likely due to their most recent common ancestor --early twentieth-century Black folk music. But then again, that source was the wellspring for nearly all twentieth-century American popular music styles.