I think CN has no choice but to drop all her incriminating information on DM. Its quite obvious that she was enthralled with DM like the others. I find it hard to find any theories which she could state to implicate MS more then anything presented thus far. It's either she spills the beans, and in doing so earn some points for herself in her own upcoming case, or she stands by whatever sick pact she has/had with DM, in which case she will still not save DM from 1st, and will damage any chance she has to walk away from all this.
My bet is on BOMBSHELL evidence being presented by CN, I bet within the first few minutes we will be amazed, perplexed and mournful for the Bosma's.
DM's D wont have much to work with but once Dungey gets up there, he will make her state she was another pawn like MS, AM, SS. Manipulated, coerced and oblivious to DM's true intentions. It could very well be that CN provides the proof MS needs.
CN needs to realize this is a serious crime and she needs to behave like a normal human being would, not like a scummy, loser, liar, lowlife, unemployed 20-something as most other witnesses have turned out to be. She seems to be the only witness who actually attended university, so maybe she has some sense of conscience, what's wrong and what's right. Killing an innocent man for a used truck? Not right thing to do. Helping DM dispose of evidence? Not good.