First of all, with the Karen deal, aren't we getting a little off track (with the fucking bitch Karen), since the original posting was about a kid and his dying Grandmother.
If it were me, I would fly to where the kid was, take him back to see his Grandmother, and if she passed away with in 2-5 days, keep the kid there, if he loved his grandmother he would want to be there for the funeral or celebration of life, and then take him or send him back to the program he was in. A program that doesn't understand family, is not a program at all.