Controlled Group: Adopting Employer no more in the controlled group, wants to terminate participation

[rodin011]

We have the following situation:

Company A and B members of a controlled group. Company A adopts a retirement plan and company B joins as adopting employer via a joinder agreement.

Company B is no more part of the controlled group and decides to terminate participation as adopting Employer of Company's A retirement plan.

Since they do not want to sponsor a retirement plan going forward the participant's benefits must be paid out.

Question.:

If there are any "standard" resolutions to execute the above, I could not find them.

I think there must be a company's B resolution to terminate the participation in the company's A retirement plan and distribute the benefits . Also a resolution of company A to approve the cessation of company B as an adopting Employer. Since B will not adopt any other plan, is this enough to justify the distribution of benefits? Or do we need some other corporate resolution(s)?

And in any case, I assume that benefits must be 100% vested.

Thank you for your help