For those of you who are still struggeling with finding a working root method, I can confim that PurpleDrake-Lite!
(PDL) metod works fine on the D722 (V10g-EUR-XX).
If you are running MS Windows, you'll find the latest official LG USB drivers here
. You do also need to enable the developer mode on your phone (e.g. https://www.youtube.com/watch?v=H_0ws9StCiA
), turn on the USB debugging mode and finally accept your computer's fingerprint before the PDL script will work properly.
To confirm the root access, connect to the phone via the adb command included in the PDL sub folder.
PS C:\Users\j> adb shell
shell@jagnm:/ $ su