When a enforcer ds-seen command is given with bad keytag then no error is given

We had people, because of a lab exercise entering "ods-enforcer ds-seen --keytag KEYTAG"
literally because that was in the lab notes. Of course they were suppost to replace the KEYTAG with a relevant one. The point is that however there is no error given, whereas this keytag would never be relevant.
There are some different cases:

• the keytag argument would never form a valid keytag.
• the keytag doesn't exist
• the key corresponding to the keytag isn't ready yet.
• the operation will be completely successfull

Currently the output is just unclear for all instances.