The Spectrum/UIM Integration allows you to move a DataCenter from one landscape to another. If there are mupltiple VCenters that contain a DataCenter with the same name, the migration of the DataCenter will fail.
Spectrum is maintaining a map of DataCenters by considering DataCenter name as a unique key for internal processing instead of the DataCenter id.
This issue is resolved with Spectrum_10.02.03.PTF_10.2.355 for Spectrum version 10.2.3. We now use the Data Center id in the internal map of data centers instead of using the name as the primary key.
Please open a ticket with Support to obtain a copy of the patch.