I agree that 1, 2, and 3 are poor options. If the OP believes he's in the right--that is, his expectations are the reasonable ones--then he should sue his partn

I agree that 1, 2, and 3 are poor options. If the OP believes he's in the right--that is, his expectations are the reasonable ones--then he should sue his partner for breach of contract. The goal is to force a settlement where the partner's share in the company is proportional to his actual contribution.