If you plan to invite an artist to make an intervention in your company, do not expect it will solve problems in quick time; an artistic intervention uncovers previously hidden issues, but it does not make them disappear.
As a leader of a company, be clear about your expectations: do you want to have a recreational event to cheer up your staff or are you looking for a deeper process that can lead to change in your organisation?
As an artist, you have to understand the value of time in any workplace; be properly prepared and keep in mind that the commission is not about individual interests, but the interests of the organisation.
Go through a proper negotiation between the company management and artist, and make a written document about what you agree.
When an artist is working in an organization, they are in the role of an artist, not as a therapist or a consult; an artist cannot solve problems concerning personal relationships or marketing, production and so on, but they can bring new insights that can lead to new solutions.