Um, there's already a process whereby private contracts, as well as all other company business is approved by a vote. It's called the shareholder meeting.

Now understandably the janitor has provided a lot less capital than deeply invested shareholder, so their votes are uniformly weighted according to their share of ownership.

I'm guessing the engineer might own about 1/10,000,000th or so of the company if she has a healthy 401K. So as long as she can convince 10,000 or so other employees and 49.91% of the rest of shareholders to go along...