Out of the box hotfixes for CADWorx do not support silent installations.  However you are able to still create a silent install by doing the following:

Change your local group policy to allow computers to run exe files in the %temp% folder (temporarily), and run the following commands:

xcopy /q /y /e "%LOCATION%\CADWorxPlant_2016_SP3_HF1.exe" "C:\CADWorx 2016\" >NUL 2>&1 
"C:\CADWorx 2016\CADWorxPlant_2016_SP3_HF1.exe" /s /install /log "%logPatch%"
del /f /q "C:\CADWorx 2016\CADWorxPlant_2016_SP3_HF1.exe" >NUL 2>&1