PC Host Installation Error Solved.
My team and I were struggling to get a PC Host added to the LAB. We knew the issue was caused by an access issue, but nailing down the exact problem was quite difficult. Now, I’ve generalized the error by indicating the Domain\User as most PC installations use custom user names instead of the generic IUSR_METRO account.
Failed to create process [C:Program Files (x86)\HP\Performance Center Host\al_agent\bin\alagentservice.exe] with user [DOMAIN\USER] windows error code 
How to Solve It:
The PC service account must have rights to Logon Locally to the system in question. In my team’s instance, we saw that our PC Service Account was failing to login and the Logon Type = 2 was viewable in the Event Viewer. Once this restriction was removed from the user, we were able to successfully add the system to the PC Lab.
The HP requirements for access for the PC Service Account aren’t ironclad. Meaning, in our instance we were able to determine that the Logon Locally right is only required to add the system in the LAB and isn’t required afterwards.