I agree, but with the proviso, again, that in order to convict, it must be proved there was a verbally agreed upon 'common design' for how to commit a specific crime or type of crimes.
So possibly there is sufficient circumstantial evidence to prove they had verbally agreed to a plan for how to get rid of dead human bodies. But that's not what MS is charged with.
Certainly, by May 2013, I think there is plenty of evidence to show they had agreed to a plan for how to murder someone to steal his truck, and that's why they were both convicted. But I don't see strong evidence they had agreed on a plan about how to murder LB.
My point was that having vague criminal ambitions, or associating with someone you know or believe committed a crime, isn't, in itself, a crime. Criminal law is about the 'guilty act', the physical action of actually committing the crime. And a good thing, because physical actions have the chance of being proven or disproven beyond a reasonable doubt.