Two music instructors start working as independent contractors together for a third party. They are encouraged by that third party to expand what they started into a nonprofit company and begin to operate on the same campus, but as an independent company separate from the initial third party.

Both are now the top officers of the new company.

The company that these two are founders of offers the same services to the same students as it did when it operated as an extension of the initial third party.

The two instructors are the only labor force of the new company in regard to its students, but each instructor also teaches as an independent contractor for other schools elsewhere.

Can these two people be considered as independent contractors of their new company, or are they, as both officers and the labor force of the company, employees of said company?

As owners of the company they are not employees unless they have a contract of employment with the company. They have a liability for certain actions as owners and officers of the company. Being members of the company does not limit their ability to privately contract their services to others unless they have an exclusivity agreement with the company, however they should not be competing with the company as it creates a conflict of interest