I consider them independent runs so I say 50/50. Your’re right too they want to make it look hard but showing one of the doors effectively makes it 50/50 so they know that over time there will be enough winna’s to keep people tuned it etc.
I’m not convinced on their independence. I am coming up with 33% on a car and 66% chance on a goat going into the reveal. While the next choice is binary when independent, the entrance condition alters the probability.