So we know that Hoid took the name after his master, the original Hoid, died. Now, from Khriss, we think that Adonalsium was likely a being, and that Hoid (or Cephandrius, at the time) was at the Shattering. I also think that Cephandrius had some sort of relationship with Adonalsium. What if the original Hoid was Adonalsium's vessel? It gives reason for Cephandrius to be at the Shattering without being directly involved in shattering it/him/her. It also has big implications into what he could be doing with his meddling with the shardworlds.