Katie Valk had the best answer of all and I agree, who cares.
Probably accidental, but if it was arson and directed at macafee, the list of suspects is long:
-Greg Faul-macafees murdered neighbor, who many people feel john is responsible for
-Associates of any of the young girls he collected
-People he threatened with his gang and goon squad
-Neighbors whose sanctity he trampled on
-Associates of macafees employees locked up in police custody while he trapsed off on his pyschotic episodes
-Gangs and thugs he hired as accesories to look tough and intimidate
-People he stiffed
-The two deaths in the states he is being sued for
List of suspects worthy of Agatha Christie, but it doesn't matter. The buildings were not insured, so its only John's loss, and really, who cares.