I tend to agree with all of that except the part where he could help her if she’d let him...I think it’s too late for that. She’s listening to someone else telling her to lie, deflect, convolute, etc. Her testimony now is practically useless because she is now known to be a liar, who does so in order to get or keep an advantage for herself; the only thing she can really offer up is info on what Fd did with Jennifer’s body, and she currently doesn’t want to do that, if she even knows. (I think she does)
She certainly is guilty, but there is no indication she was the actual killer, nor does is appear she was with Dulos when he ambushed his wife. In terms of culpability, he is the more culpable based on the facts revealed to date. Thus, she could have made some sort of deal. Whether she still can remains to be seen.
Yes, she is a liar, who has given inconsistent statements and I can certainly understand if Coangelo is done with her. She will be vigorously cross-examined if she does testify for the state. That does not mean, however, all deals are, or should be, off the table. Prior to AW3, I thought Bowman might have been able to negotiate a certain term of years. Now, that kind of deal may be too late, and there may be no more negotiations to be had.
Never say never, however, because stranger things have happened in criminal trials. As a very experienced prosecutor was fond of telling juries during close,"You have to go to hell to find witnesses to convict the Devil." In other words, better to make a deal with a very bad person than to let the ultimate wrongdoer go free. Coangelo is an experienced prosecutor. IMO he can prepare his witnesses for trial, although, again, MT's truthfulness to date has been sorely lacking.
This question is something that will be answered in the coming days, although at this point, if I were the prosecutor, I would most likely be turning my attention to KM. He may prove to be someone who will not hold up to incarceration well, especially knowing FD and MT are walking free. Again, I would speculate that any deal will require some term of imprisonment, will require complete cooperation, and will be offered to him only if he is determined by LE to be the less culpable defendant, which he appears to be. He may jump at the proposed cooperation agreement that MT apparently foolishly turned down. It all boils down to what other evidence the State has and whether it determines his testimony will help convict the Devil.