To restrict any user from utilizing a 3rd party software on the iSeries, just change their authority to the library/objects the product resides.
RVKOBJAUT or GRTOBJAUT
or CHGAUT for IFS
CHGDLOAUT for DLO
Those command will change the authority to access the objects.
Many third party software products also have internal settings to set authorizations to actually use specific functions. If that is what you need, you will need to consult the user’s manual for your software to determine what to change and how to change it.