Solution is per:
1) manual workaround via: https://ca-broadcom.wolkenservicedesk.com/external/article?articleId=14576
This is a manual workaround to make use of CLI to purge off single/specific entries from the device DeviceIPAddressList table attribute.
2) The underlying functionality is in parts "FAD"/functioning as designed by default -
but CA Spectrum with release R10.2.1 and higher already covers an improved functionality.
This is triggered/managed via attribute "UseRPAForTrapProcessing" for the
SpectroSERVER's ./SS/.vnmrc settings: UseRPAForTrapProcessing=true
Using this setting will then control the inbound TRAP processing to assert the TRAP to only those devices covering in the IP-redundancy (Primary Address list) the given TRAP source IP-address.