One of our trackday group recently took out insurance for a day at Thruxton in his M3P and paid £194 on a £50k valuation with £2,850 excess through Moris.Ive done a lot of track days and did some circuit racing (in a lotus Elise). IMHO £300+ on insurance is a bit on the high side, but I think it probably reflects the repair costs for something like a Tesla. When I was doing a lot of days, I used to get it included as unlimited track days on my normal insurance via a specialist for a few hundred extra. I think a number of other policies are available allowing something like 4 or 8 days for a little bit more - I am not sure if such polices are available on a Tesla.
I have never heard of insurance being included on the cost of a track day, it's an individuals decision on whether to insure or not.
TEVO: was that the official timer or one you made from the video?
I don't know why there should be such a difference between that quote and @Obliter8 but maybe it was the excess or driver age, history etc.?
Official timing isn't done on school days so I took it from the video.