Are you using WDS (Windows Deployment Services) and MDT (Microsoft Deployment Toolkit)?
If not, you should look into them...
WDS is Windows server role and MDT is a free from Microsoft. They will make your life so much easier when it comes to imaging machines.
MDT injects the drivers as part of installing windows and automating everything.
This will also your answer your question...
I have an application package for 3D drive guard and Hotkey installations.
It may differ between versions, but this is for the latest versions for the EliteBook 8560p
Extract the 3D drive guard files from the HP sp64144.exe (or whatever version) (use the likes of 7zip).
You should have a setup.exe and driver files..
For you command line for silent install use: setup.exe /quiet /norestart
Do the same for the hotkey package sp56876.exe which should give you just a setup.exe file.
Use the command: setup.exe -s -v"REBOOT="ReallySupress" /qn"
As for the touchpad driver, i haven't done that one yet...