Why was it a problem that number 11 was already in the CMDB? If it was already there, and had the correct state, it wasn't a problem.
I think you are saying that you deleted the data corresponding to the host from the CMDB? If so, you have done exactly what you are not meant to do and modified the Discovery dataset. Resync is the correct way to resolve that.
The problem was ComputerSystem and SoftwareServers, etc. did not have the relationships to the Application. I'll kick off a resync. Thanks, George