From sleuthing, we know Tom and Mark are friends and Dean is friends with Tom's brother, so I think it's likely at least these three are connected somehow.
Sturgis's father has also said MS was going to visit TM and they disappeared together, so those are definitely connected. It seems likely DF is connected somehow as well. There doesn't seem to be any online footprint for JTP at all, so who knows about him?
This ia the link i was referring to about Kensingron when i was researching comments http://www.philly.com/philly/health/addiction/A_hidden_heroin_hellscape.html?mobi=trueKensington is a neighborhood in Philadelphia, not a separate town. It is notorious as a drug haven. Kensington is about a 30-45 min drive from the Bucks County areas where these teens disappeared from.