Point in time recovery Oracle 12c with TDPO
As the error message already states, this is not an Oracle issue. The backup piece simply can not be found on the TSM server where Oracle searches - based on the tdpo configuration.

Maybe it was created with a different tdpo configuration under a different node name or in another filespace. Maybe it is simply not there on the TSM server.

You can query the contents of TSM for this tdpo config with:

tdposync query -tdpo_optfile=/opt/tivoli/tsm/client/oracle/bin64/tdpo.opt


Most likely you will not find DB_954446866_1042_1 in the list, and that is the problem. Ask the TSM administrators to search for DB_954446866_1042_1 in their catalog. If they find it in a different filespace, or registered under a different nodename, you can restore it by collaborating with them and using the correct tdpo configuration. If they can not find it, you are out of luck as that backup simply does not exist on TSM.