UPDATE: this appears to be a case of user-error
the ldapsearch was not pulling the entryUUID because of a malformed search line. The required syntax for the "attrs" (last part of line) should have been '*' '+' when making a dump. Omitting the '+' caused LDAP to regenerate the entryUUIDs on the consumer, which would then subsequently mess up syncing operations
Perhaps slapd should at least warn when syncrepl is configured in a way that entryUUID and entryCSN are not replicated.
p.