I highly doubt they'll walk on the murder charges. One of them may eventually get a sweet deal, but if they continue firing lawyers, and insisting one being tried together, both will go down for the loooong haul.
They'll never walk from the secondary charges the state is sitting on. They have enough to send both away for about 10-15 years. The brutal part about these two idiots is that to prove their innocent, they have to admit to doing numerous other felonies. ie. Arson, indecency to a corpse, failure to report a serious crime, all sorts of stuff.
Don't expect to be seeing these dopes anytime soon.