Hub rename requires a cold start of the hub: stop Nimsoft service and then start it back up.
In the event that probes on the newly renamed hub show red-lock icon, right-click the probes and select Security->Validate.
If 'origin' on hub was not set and the hub's name was being used as 'origin' then you have to update S_QOS_DATA table using SLM tool to reflect your new hub name.
Please also see the KB article on validating probes with the PU command:
KB47923 : Is it possible to re-validate a probe via the PU Command?NOTE: Any queues / configuration pointing to the old hub name will need to be manually changed.