Top Secret TSS GENCERT client certificate and TSS EXPORTed in PKCS12 format to a dataset is rejected when trying to import into zowe keystore saying it's not a valid certificate.
Top Secret TSS GENCERT root certificate and TSS EXPORTed in CERTDER format was accepted by zowe without issues.
Release : 16.0
The TSS EXPORTed client certificate is accepted by many applications without issue.
Import the certificate to a browswer keystore like (Firefox, Chrome, Edge).
If the import is successful, then this proves the certificate is valid.
Export it back out from, then import it into the zowe keystore.
Please refer to your browser documentation on importing certificates into it's keystore.