Harvey took Luke from his bike ride but Regali (the mob guy) killed him. Harvey had a thing for boys and when he saw Luke, he couldn’t resist so he kidnapped him and tried to molest him by bringing him back to his place. Regali walked into the scene while this was happened. Luke saw his face and for the fear that he might ID Regali, Luke was killed. This explains why there was no ransom note. He said that in his line of work, he has to deal with sickos, molesters, etc. The ‘businessman’ he was talking about is himself…hope that clears everything up for you!!
I’m positive that it was Regali that killed Luke…poor Doggett finding out what sick thing happned before his death…
If you want me to clear things up or have any questions, feel free to ask…aiight then