This is a very sensitive topic as any regurgitation (vomiting) in snakes is bad.
This can be caused from high amounts of stress on the snake post meal.
Handling the snake too early after a meal can cause it to regurgitate.
Temperature can cause issues when it is too cold it slows down digestion rate. The meal will begin to rot in the snakes gut before it gets fully digested and this will cause it to regurgitate.
If the temperature is too hot, it will stress the snake to an extent that it will throw up. Snakes get nerve damage if their temperatures are too hot and it is usually irreparable.