No motorcycle tech would claim to have worked on any bike for 18 hours and returned it to a customer in that condition. There is no cause, need or reason to drain coolant to work on an issue with brake lights. If there were, in fact, air trapped in the cooling system, it is more likely that the temp gauge would read no or very low bars since there would be no coolant contacting the sensor. That would also cause the fans to remain off. The fact that the temp goes high when stopped and takes longer to drop once moving again indicates that the fans are not working. Since the "tech" was looking at electrical stuff, it makes more sense that they inadvertently/unknowingly/stupidly disconnected the cooling fans and failed to fully test the bike once they were "done" with it. It saddens me to see you going through this Gene, but I am convinced that whoever you've had working on the bike is an incompetent boob. I sincerely hope that whoever you take it to next is able to resolve the issues (both new and old) to your satisfaction.