I believe that health insurance payments from a place other than your employer are equally valid for child support purposes. The child support calculation is based on the INFORMATION, not on the Financial Affidavit form itself. So...although non-employer health insurance does not belong on the "deductions from pay" section of the Financial Affidavit, they do belong further down the form under "Insurance" expenses. Be certain that it is clear that this insurance is for the Affiant only--not the child subject to the support obligation being calculated.
It doesn't have to be employer-sponsored for it to be deducted.
THESE COMMENTS ARE NOT LEGAL ADVICE. They are provided for informational purposes only. Actual legal advice can only be provided after consultation by an attorney licensed in your jurisdiction. Answering this question does not create an attorney-client relationship or otherwise require further consultation.