This issue is resolved in CA Performance Mangement 3.6.6, form the 3.6.6 release notes for defect DE407756
Symptom: When moving a SNMP device between Data Collectors, the polling config for the CAMM device would have it's associated DC itemid updated, causing issue with CAMM poll processing. Also, when checking the polling config for a CAMM device, it could show all the SNMP components on the device also.
Resolution: Updated the move device code to not update the CAMM polling config's DC itemid. Updated the code, that determines what goes into the CAMM polling config, to only include CAMM components.