The ClarityClient2021ClientRevit.exe is built with InstallShield, which supports most MSI-style options, including passing them thru to the MSI.

See this link for install options for the Clarity Client installer: 

https://docs.revenera.com/installshield21helplib/helplibrary/IHelpSetup_EXECmdLine.htm

For those who are security-minded, there are some nuances to understand about the BIM360 Security Model, when used with Clarity or with any BIM360-enabled tool.

In the older BIM360 Teams-based approach, Clarity used what is called "Three-legged-Oauth" to connect to A360/BIM360. This meant that we requested access, and you supplied a user whose credentials would be used to access A360/BIM360. The Clarity server at your facility could see ONLY the hubs/projects that the designated user was able to see. 

In the new BIM360, Autodesk created an additional step - an application-based permission for Clarity. BIM360 administrators must enable access to