No. A commercial relationship does not create an eligible family relationship for derivative treatment.
Identify the actual principal and relatives
Money and family are separate questions here, and blending them is the usual error. Someone who put capital into the earlier venture alongside the investor is a co-owner, not a relative: a business partner, a co-signer on a loan, and a shareholder in the old holding each need their own basis for any U.S. status they want.
The derivative class is narrow. The investor's spouse and unmarried children under twenty-one may generally be included as derivatives of the principal, subject to the rules governing their own admissibility and processing. Age matters more than families expect, because a child who turns twenty-one before the relevant point can fall out of the derivative class altogether; track each child's date of birth from the start rather than discovering the problem at interview.
Derivatives who obtain conditional permanent residence hold it on the same two-year terms as the principal and must be accounted for when Form I-829 is filed. Every family member needs their own civil documents, including marriage and birth records, prior name changes and any earlier immigration history, and none of that is established by the source-of-funds evidence however thorough it is. Derivative status is borrowed status.
The principal's case must still meet the category on its own terms, with lawful capital irrevocably at risk in the qualifying new commercial enterprise, the statutory amount applicable on the filing date, at least ten full-time jobs for qualifying U.S. workers, and genuine management or policy-formulation participation. Confirm those amounts and procedures from official material for the filing date, because if the principal's petition fails no relative acquires anything through it.
Ask a U.S.-licensed immigration lawyer about each relative's own position.