When the installer is elevated to admin priveleges in a split account system, the installer will move over to the admin account, then install and check for SteamVR there. When being run on a non-admin account that has SteamVR installed on it, when elevated, the installer will instead target the admin account and find a lack of SteamVR.
Two available tested workarounds:
Temporarily grant the non-admin account admin priveleges to run the installer, then remove the admin priveleges after installed
Copy openvrpaths.vrpath from %LocalAppData%\openvr\ to C:\Users\Admin\AppData\Local\openvr\ before running the installer to set the target correctly on the admin account
When the installer is elevated to admin priveleges in a split account system, the installer will move over to the admin account, then install and check for SteamVR there. When being run on a non-admin account that has SteamVR installed on it, when elevated, the installer will instead target the admin account and find a lack of SteamVR.
Two available tested workarounds:
openvrpaths.vrpath
from%LocalAppData%\openvr\
toC:\Users\Admin\AppData\Local\openvr\
before running the installer to set the target correctly on the admin account