If he's "not really your friend" and a social media follower I'm not sure how this is someone who could be of any benefit to you. If someone I barely knew asked me the same question I would just go to the person and say "Hey someone was asking me about why you're not talking to them anymore." Of course, that's me, and I don't socialize like everyone else. I'd suspect that most normal people would be offput by that question being posed by someone they don't really know. Especially in this context since it's just a social media follower. I don't use social media so I don't know if having a follower is a big deal but I somehow doubt that follower = trusted friend. To me that just sounds like the equivalent of a follower on this site, someone who enjoys posts enough to follow someone but ultimately doesn't know them at all.
I believe I said this in another thread of yours, and while I do not think this is necessarily the best advice, it's the best that I can think of: Asking them directly, and/or state that you want to restart your relationship.
