If an agreemnt releases one from a judgmnt, & the creditor then defaults on the new agrmnt, is there any way the creditor can collect on old judgmnt?

I agreed to buy my partner''s 50% shares of our business. I defaulted before any shares transferred. He sued, won a judgment. Before attempting to collect, he agreed to buy out my shares at a steep discount, and releasing me from the judgment. Then HE defaulted. Is there any way he can collect on the old judgment? No shares have transferred. Aren''t we back to square one? He currently plans to sell the company. No shares ever transferred, so I believe I am entitled to the full value of my shares. Or I could sue to enforce the more recent agreement. If the old judgment was agreed to be dropped in the more recent contract, is there any reason it should be a factor in our negotiation? Thanks!