Correct me if I am wrong here - but I feel like the zero could handle having a different UID lease per tenant, it doesn’t do much with it other than reach quorum with other zeros about that number and report it back to the alpha that asked for it.
Since the storage is handled by predicate and not uid, it doesn’t matter if a uid is shared between tenants, you wouldn’t be able to select any other tenant’s predicates from that UID.
Edit: sorry - speaking in the world of the upcoming multi-tenancy of course.