A half a million US dollars can very,*very* comfortably support several kids in Central/South America.
After having done this,the *serious* cash will start flowing somewhere down the road.
There's no reason for these kids to be admitted to this country except,perhaps,for the funeral (which I think has already occurred).
Costa Rica is actually quite affluent, peaceful & pleasant for Central America. Many Americans go there to retire. I'd rather live in San Jose (Costa Rica) than LA, Detroit, Newark, New Orleans, or lots of other US cities.