Op has no basis for a non-custodial waiver. if NCP does not complete application, then application will be incomplete and student will not get any aid.
NCP is responsible for the information that is put into the application. If NCP lies then student will lose aid and parents will be responsible for repaying school.
If op cannot trust the NCP to fill out forms honestly, then student needs to apply to schools that will not ask information from non custodial parent.