Diamond drove Mackie and Chloe to each school Vernon had confirmed was safe for them. Vernon made sure that the Principal of these schools had no history of connection with Vincent or any of the Gray family. The students' family backgrounds were more diverse to minimize the probability of the parents having close contact with Vincent.
Vernon made a great deal of effort just to ensure Mackie and Chloe's safety, so Diamond thought she should at least help him by assisting her boss' favorites.
They arrived at the first school located around the corner of Manhattan. It was a private school inside a tall building with no front or backyard. It might not be as exclusive as Mackie's old school because Mackie's old school was inside a gated community with a big indoor gym, huge outdoor track, garden, et cetera.
But it was still a good school that can guarantee Mackie's safety.