sorry just updated my post with quote
No worries.
To answer with MOO to your question if that's ok, MS being used speaks to how DM seemed to operate. Never get his hands directly involved in something bad if he could avoid it. Try not to have direct links to something bad. So if he knows MS sells drugs, has a criminal record and basically just comes across as aimless, why not get him involved with stealing a truck and bringing a gun along? Get MS to come with him on the test drive and bring his gun for "safety" and then DM ends up using the gun. Then he can just say he really wanted to just test drive and buy a truck but his drug-dealing friend brought his gun and killed TB.
Again, MOO.