(g) No relocation payments or relocation advisory assistance shall be provided to a person who has not provided the certification described in this section or who has been determined to be not lawfully present in the United States, unless such person can demonstrate to the displacing Agency's satisfaction that the denial of relocation assistance will result in an exceptional and extremely unusual hardship to such person's spouse, parent, or child who is a citizen of the United States, or is an alien lawfully admitted for permanent residence in the United States.