Yes, that surprises me. Slave tells that it will refer the change to master, but master does not receive any information. I use debug level -1, but cannot find the change arrives in master.
I forget the exact arguments you used, but it's probably your job to follow the referral. i.e., you should be running ldapmodify -H ldap://master/...
But certainly if you're not seeing the change at the master you can't be surprised that it's not at a slave!