The exact people who needed it most couldn't get it
The ones who couldn't get it were the people who needed it the most
そうですねすぐ売れ切れてしまいますね
The exact people who needed it most ( 一番必要だった人だけが)couldn't get it( 買えなかった)
The ones who couldn't get it( 手に入れなかったけど) were the people who needed it the most( 今一番必要だった人です)