Ask HN: How to renegotiate with a $6M startup as a co-founder?

I have to consider leaving or renegotiating with a one-year-old $6M ARR startup I co-founded due to disagreements and disappointments over what was promised to me.

I as the marketing founder am entitled to 20%, while the other technical founder who coded it is entitled to 80%.

I worked on it from scratch, for about 12 months, without pay.

When starting, we verbally agreed that I get 20% of the company after one year, and that's it.

Now the written contract draft can claw back 10% from me, even when it's vested, and then squeeze me out.

Is it reasonable to insist on 20% and full protection for what I own and its future benefits, with no strings attached and a guaranteed board seat, so no squeeze-out is possible? - They still think it's unreasonable and a red flag for future VCs.

I don't want to leave now. But neither I want to risk leaving empty-handed for working insanely hard already and continuing to do so for more years.

What would you do, besides getting a lawyer?

Thanks!