ANSWER:
Islamicly, it is his word against yours.
If he had divorced you 3 separate divorces, after each divorce he reconciled with you and revoked the divorce then divorced you again after some time, these are 3 separate divorces and you are divorced from him and can’t live with him as he is non mahram to you.
If he denies it at court, you have no other option other than filing for khulu and paying him his dowry and he will meet Allah as a liar and a thief.
But if he divorced you 3 in one setting, this counts only as one.