Did they say anything about immigration status? Probably not part of this but border crossers are afraid of being deported and might clam up if they knew of child labor violations or anything else at work.
Guy I knew at work was from Mexico as a boy in the 80s. Totally legal citizen later. His whole family had to produce a certain number of “flats” of berries and other produce in Michigan while legally migrant temporary laborers. He as a 9-11 year old (along with his sisters) helped the family with the stoop labor every day or they wouldn’t reach the quota. He told me “those flats were big and had to be filled.” Family never took welfare.
I wondered about immigration status too.