It is also puzzling since there was no Lab reports for DNA or Prints on the guns at least yet or in that discovery. There would have been previous prints on the guns just from handling, if not from the night of the murders. Did they wipe the guns off that thoroughly, but not wipe off the knife good or at all. They did make mistakes.
Why bother keeping the knife or the guns when they could just have gotten rid of them all. Seems those items meant somethinng to them.
I assume JW said that G4 was at the scene in some capacity so they probably do not need anything that proves G4 was there. It is nice in a trial to have some independent DNA/forensic evidence but JW's confession will probably seal G4 fate as far as him being there and being complicit. Complicity in aggravated murder is considered the same legally as being the principal offender.
From everything I have read, yes, if you are complicit, you are as guilty as the perpetrator... That said, the Defense does not have to prove anything, the Prosecution has to prove complicity. To a juror that can be in the eye of the beholder....