How would they possibly know the terms of either offer as former employees?
Btw this applies to those who are still employees too (if they explicitly bought vested options)
My advice to anyone joining a startup - if you have the negotiating power, insists that you must pre-exercise and purchase all options immediately when you start your job. You must put some money, but if you don’t believe in the company, why spent years there. Most companies don’t like this and their VC will object. This is why I said “if you feel you have the power to ask that”. If you can’t do that, exercise as soon as they vest
Edit: to clarify - this isn’t same as accelerated vesting. Vesting rules still apply - but you become a shareholder with appropriate rights.