Majority shareholder wishes to sell to other two. I had a brief discussion with all 3 last month about the tax ramifications.  Lately, the majority shareholder has called me for advice. He claims that relationships are cordial. I have not separately talked with the other two. (I prepared all 3 individual 2022 tax returns and the S Corporation 2022 and prior.)

But, he (the majority HS) said to me yesterday that the business attorney told him that "the CPA" added a provision in the shareholder agreement two years ago about how to value the stock were a sale to occur. I have not talked with the attorney. There is a possibility what he relayed to me was not accurate. Nevertheless, I feel something could be amiss; perhaps the attorney is deflecting or shifting responsibility to me. This news gives me pause. 

Also, I was told (by the majority SH) that the other two shareholders have considered terminating the company.

I don't have a formal service I am offering, and no engagement letter has been sent.  I don't plan to get involved or have another discussion again. I will say something such as "the valuation and agreements are up to you", "I will not advise any of you" and once you decide on the stock sale price, I will become involved with your tax planning.  This seems less than satisfying.