When Jack made the 'rooming' remark I thought he was just being tongue in cheek, as I was very familiar with Dylan's biog and was pretty certain that the two had never roomed together. However...

Dylan (then still the not so mighty Zim) first heard a batch of Jack's records in Dinkytown ('59 probably) and was very impressed by them.

When, in early '61 he met Jack in person at Greystone Hospital when both were visiting Woody, Dylan was star struck and started following Jack around 'like a puppy dog'. When Jack, who was just back from Europe, took a room at the Earle Hotel in Washington Square, Dylan also took a room there, a few doors down. So, effectively he did virtualy room with Jack for a short time.

btw, Dylan is not Dylan's 'stage name'. It is his legal name, changed by deed poll in '62. Both his former wives were Mrs. Dylan and his 5 children were all given that name.