You would need to inquire directly with HTC or Valve to work out a deal such as this. As far as I know this is not a thing as they have beta testing and community reporting, therefore eliminating the need for private/paid testing in most scenarios.
If you still need help or have further questions, reply in the forum and I or another member will attempt to help you ASAP! _____ I am NOT an HTC or Valve employee. If I have helped you or resolved your issue, please accept my answer as the solution. _____ "Welcome to the world of VR" -Mango