Dear Jerry,
No other Christianity is mentioned in the book, right? (Except the Pope.)
Besides the Pope, I can recall (St.) Francis Xavier, and St. Augustine and "dear Jesus" are mentioned. Also two of the three Magi (Balthasar and Melchior) are mentioned by name and the third Caspar may be referred to (the dark gardener who Kinbote arrays in eastern finery).
I'm not sure what you mean by identifying the young priest. Are you thinking he's some New Wye character transformed in Kinbote's delusion?
I do think all of Kinbote's Zembla is populated by characters from New Wye. Sybil, Sylvia and Disa are the same person; Shade-Kinbote-Charles II and Gradus are the same person. The Countess de Fyler and Aunt Maud are the same person. One of the few who seem to have no reflection in Zembla is Hazel.
Carolyn