AD, FWIW, I have never seen any reference to MS being a "gang banger". MS did graffiti, but has it been officially linked to a gang?
In my opinion, their are only two types of graffiti; that done by street artists meant to improve the landscape with some art and/or beauty, and that done by egotistical brats who want to mark their territory with spray paint the same way that animals mark their territory by peeing on everything, and they do not care if ruins the landscape for others.
Even if his graffiti was not established enough to tie it officially to a gang, wasn't it determined in a blog that the connection between DM and MWJ was that MWJ hung out at MS's house regularly enough to be (social media comment-worthy) friends with MS's sister? Wouldn't that be MS's gang connection?
And now that I think about it that way, and we're on the thread of MS being a dupe, I would think that it would be more likely that the one who would have been able to dupe or pressure MS into committing a truck theft and murder would have been his pal MWJ.
Here's my scenario for this thread: MS is a fairly regular guy, he smokes a little pot, gets into a little trouble here and there but nothing too serious. He is friends with a guy he gets his drugs from, even though the guy is a total gangster, shaved head, face tattoos and everything. He probably thinks that it makes him a bit of a badass to hang out with such a tough gangster, and he probably tries to impress the gangster by telling him about how he is also friends with a rich guy who has vehicles and planes and properties and all kinds of crazy tools and machines that most people have never even heard of, like a portable incinerator even! He is building a huge hanger that is currently empty and even knows a girl who went missing.
The gangster likes what he hears and hatches a plan whereby he will give MS a gun and a plan on how to jack a vehicle the next time that they go out car shopping together, with the instructions that if anything goes wrong, to kill the owner and dispose of the body in the incinerator, no doubt the suspicion would fall on the guy with the missing friend, especially when MS was instructed to leave all the evidence at DM properties. I would guess that he forgot to give instructions on how to scatter the ashes after so that LE could not find them. Then I imagine that TB's truck would be too hot for the gangster to drive yet, so he could have easily gave orders to MS to stick the truck in one of those trailers he told him about, and to stick it at another property. And if DM gives you any trouble, show him the gun and remind him that you know where his mother lives and how to make people disappear.
I guess in my scenario, MS is more pressured than duped, but I think in real life, more people do stupid things because of pressure rather than by being tricked into things, like in a sitcom or something.
All of this is my opinion only.