Standalone installer for Password manager client
You may want to create an install for the Netwrix Password Reset client (Logon Prompt Extension) with no user interaction so that you can push it out through a GPO.
For installation of the client via Group Policy, you can use the separate prm_client.msi installer.
It can be found in the program installation directory after installing a server part (by default C:\Program Files (x86)\NetWrix Password Manager).
GP installation is described in the procedure 4 page 11 of the Administrator's guide.