The dated official terms, the government's processing-fee receipt, the vetting outcome notice, the government's gift instruction and the transfer confirmation matching it exactly. Payments to any private party are not the gift.
Every payment matched to a government instruction
Because the program involves large transfers, the family's own record-keeping is its protection. Save a dated copy of the program page and FAQ at each step, because terms may change between the fee and the gift. Keep the receipt for each US$15,000 processing fee, one per applicant, showing the government recipient.
Keep the vetting outcome notice, and then the gift instruction that follows a successful vetting, including the recipient details and amount. The transfer confirmation should match that instruction to the dollar. If any consultant, agent or employer proposes to collect the gift or the fee on the family's behalf, treat that as a reason to stop and check the official process; the published framework describes payment to the government, not to intermediaries.
Keep private professional invoices in a separate folder so no one later confuses a service fee with the gift or the processing charge.