A gift to the U.S. government plus a processing fee. A gift creates no asset and no claim, so the household should not expect any of it to be recoverable.
Compare it against the routes where money buys something
Think about it as a balance sheet question. When a treaty investor spends money, an asset appears on the household's side of the ledger: premises, equipment, goodwill, a company that could be sold to someone else tomorrow. When an EB-5 applicant commits capital, the ledger shows a holding in an enterprise, which may lose value and may also come back.
A gift to the U.S. government records no asset at all. The household's net worth simply falls by the amount paid, plus the processing charge, and there is nothing on the other side of the entry.
For a couple whose money came from a severance package, that arithmetic is the decision, because the sum spent here cannot afterwards buy a house, fund a business or support a retirement. Confirm the current figures on the government's page on the day you decide, and read whatever it says about repayment in any circumstance.