Change your flight. If you do not you have to pay 6 X 500thb overstay fine when you depart at the airport (3,000 thb). The risk is, if you get stopped by the police for any reason during those 6 overstay days, you will be arrested and deported.
Why in the world would you think someone on Facebook could factually answer your question? Name One person in this group that can factually tell you the correct answer to what are your chances? Instead of being a bully, why don't you go to the factual source and look it up or perhaps, even better, call and ask exactly what they will accept. There isn't one person here that can give you a factually answer. Helen Rimmer already gave you the answer to check the website for the Thai embassy you will be dealing with.