Here is my guess---- and only a guess based on what is most common from following other cases.
I don't think it was a drug overdose (cause he was in the river). I don't think it was a serial killer (its almost easier to think there is one big bad person out there than to think about SO many bad people out there all around us, but I don't think it is reality in this case). I don't think it is a "hate" crime of someone who didn't like him due to his race, creed, color, sexual orientation.
What I do think is that it is someone he knows. I think they maybe had it out (jilted, called out, told off?) and he got strangled. I think they dumped him in the river after he died. I think the police have already questioned this person and pinged their phones. I think that the reason the investigated that area was because of phone pings (maybe even killer and Joeys phones both pinging in the area). When he was found there, it was immediately considered suspicious because killer suspect's phone was already proven to be there at some point in that night after Joey went missing. And killer suspect probably lied and said he was home, but the police knew his phone pinged somewhere else. The same somewhere else that Joey's dead body was eventually found.
I guess we will see. This line of logic is (unfortunately) pretty common around these parts (the Websleuths parts, that is). If I think about how close really bad people are to every where we go, it makes me terrified. I am sorry that it seems like Joey's path was crossed with one of those people. I really hope that the police are on to whatever happened to him. I have a feeling they are. I hope the killer is arrested and convicted. I hope that justice is served, in the form of a very long sentence behind bars, where killer can spend the rest of his days.
Yep. Just my opinion.
Strangulation would have shown up on the autopsy.