its not what it seems mercedes TD300 glow plug no start

I made this video after a battle defining the issue when everything pointed to something else initially. I didn't film the whole process as that would be a feature film... so this was some basics of "remove and isolate" process and to find it was not a typical glow plug relay box issue. A common issue it was, but not where suspected. I really thought it was going to be in the ignition somehow as I had just been under the dash to replace the heater/vent hose that goes right over the ignition switch which was already a little jicky. Assuming and guessing does no good what so ever, only retrieved data and an elimination process to help narrow down where to find the issue.