I think most of us are not holding our breaths. However, I do think that if someone within LE plays Good Cop with her and strokes her narcissism, she's opened her beak so many times, she will do so again. She's going to have major mental issues being a prisoner. She's older than most of the women who will be around her. She's used to a middle class life. She was, until just over a month ago, acting as the mom of a family, with a husband. If she's the type of personality I think she is, she's going to start cracking and yapping - but will she say anything useful? Hopefully, her own attorney will be able to get it from her and tell her that she needs to negotiate. If she wants to go back to her "It's an accident" defense, then she needs to say where the body is, exactly. She needs to play dumb and scared.
I haven't been in a jail for about 5 years (I've done research in jails and mental hospitals, including Atascadero State Hospital for the Criminally Insane) so I'm sort of going by that and what I've seen work. I think she'll respond more to a male interviewer (just a hunch) and to little presents like food. She wants to tell. She wants the attention. She should do herself a favor and plead to a lesser charge in return for revealing where Gannon is. When I was working in jails and mental hospitals, there were a lot of people who were in their mid to late 20's and there are generational shifts in how people handle things (TS seems to think she's a millenial, is my point - if so, then she feels really butt hurt that she's forced to wear a certain thing and will not like the food).
If Gannon's body is going to reveal something really sinister in what she did...she probably is going to stay quiet.