looking at the videos, seeing it cut out suddenly, it looks like an electrical or ignition fault of some kind. If you have purchased another TCI box, give it a try. It is possible that some of the components on the board aren’t soldered in very well and fatigue from constant vibration can cause some of the solder joints to become intermittent. However I would expect you would have problems at more than idle if that was the case. Still it is worth a try, especially if you have bought another igniter. If it is the 12 volts and ground that are intermittent going to the igniter, you could try hooking up a test light to those signals at the connector. There should be a solid voltage and ground going to the TCI box. Could also be wiring from the pickup coils or the wire going to the coil. You’ll have to check these for continuity with your meter. When you are checking the wiring, tug on it a bit while you have the meter hooked up. Does your bike have the side stand relay? If so, disconnect that relay. Given that the bike has been completely rewired, I am thinking there is dodgy connection somewhere.