Sorry to break this to you, but your code is a programmer's worst nightmare. Like, I-wake-up-in-the-middle-of-the-night-sweating kind of nightmare. It is not exactly readable and there are tons of unnecessary repetitions, which make it hard to debug. Here is a suggestion which is not directly connected to your question, but will help you debug your code nonetheless:
Use lists/classes/dictionaries instead of single variables to create the desired behavior. That way you won't have to write endless if/else statements for every single object. Instead you will be able to set attributes from lists .You can think of it as a table where you have objects in the horizontal axis and attributes in the vertical one. Then it is just a matter of changing these values by defining a single function that takes the selected object as an argument and iterates through said list/dictionary. Or use classes where you set each attribute only once. Right now you have to check what each car's type is multiple times. What if you want to add more cars in the future? will you rewrite the same code 1000 times?
Having said that I think that the problem might be the fact that your condition for a car exiting the scene is too restrictive. I mean, if the rotation is between 359 and 360 degrees and if it rotating is true. It might be the case that the degrees are never registed correctly, thus preventing the current car from leaving the scene. Your code is also unresponsive, since pressing the buttons sometimes does nothing or is very slow at best.
I would go for a simpler approach where I would put all available cars in a list and when the button is pressed, I would check the previous index in that list and trigger the animation of the car corresponding to that index. Then I would instruct the current car to turn towards the exit point (instead of waiting for it to turn on its own) and leave. Right now the game waits until all conditions are met before it does anything, which is buggy.
If this comment answers your question, let me know so that I can turn it into an answer.