You're trying to turn an ALLEGED "promise" into a legally enforceable "contract".

Yes, it probably sucks for you at the moment.

Yes, you were likely taken advantage of and used.

Yes, he likely worked you harder than a "government mule".

Sorry, a mere "promise" is unenforceable at law.

I wish you well, keep working hard, your day will come.

In the future  get it in a WRITTEN contract before you do anything for anyone.

Dionne Warwick sang about your problem, "Promises, Promises":

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