First of all ,
@Mr_nobody and other guys that I know, I really miss you guys , been pretty busy with business and so on. But the good news is on the way. I'll be here more often.
Back to the question. how many co-founders? how many of you are identified as an essential member ?
If either essential member is going to withdraw from the team or his interest in the startup and that is before final decision by IRCC, then you have to inform IRCC and msot likely all other application will be refused. This is also the case when an essential member found inadmissible by IRCC or does not meet the requirement, the rest of application will be refused.
If any of you identified non-essential in the commitment certificate, whether or not you yourself withdraw, or found inadmissible , this would not affect to the rest of the team.
If you want to stop working with the team before become a Permanent resident, ( when you have PPR, you still consider foreign national ) You have to inform IRCC about it otherwise it could be interpret to withholding the material fact and subject to S(40) and even if you obtain PR or even your citizenship status, if IRCC find it , they can revoke it.
My advice to you guys is to try to solve the issue with your team. if thats not a case anymore, inform the IRCC about it and see whats their decision.