I've been in roughly this situation, where the founder of a small company made grandiose claims and would say anything to get the sale, get another round of investment, get his way.
Reevaluate any promises he's made to you or any agreements you think you have with him. If you have a manager between you and him, same goes. A manager who is much closer than you to his dishonesty and is OK with it is going to act the same way to you, or claim to be on your side but, gosh, was overruled by the boss.
Now that you know you can never trust your bosses, it's time to find a new job.
Reevaluate any promises he's made to you or any agreements you think you have with him. If you have a manager between you and him, same goes. A manager who is much closer than you to his dishonesty and is OK with it is going to act the same way to you, or claim to be on your side but, gosh, was overruled by the boss.
Now that you know you can never trust your bosses, it's time to find a new job.