Please first check if your version is supported by your OnGuard version. Easiest is to go in ClearPass to Administration -> Support -> Documentation, there you can find the list of supported client software detection. The McAfee Agent is probably under Patch Management, then McAfee ePolicy Orchestrator Agent.
If your version is there, and it is not detected, please work with your partner or Aruba Support to investigate the issue. In my experience, it helps a lot if you can make the agent binary available for Aruba Support. If you supply that at once, it will speed up the process.