Redleo12, I sympathize with your difficult situation, I really do. What I am about to say is going to sound harsh, but it is not meant harshly, it is just my honest opinion.
Honestly, I dont advocate saying anything, because what happened to YOU isnt really a big enough issue to go to management about. What is happening with Maggie is, because she is responsible for Connie's conduct. But the truth is that, if Maggie is the manager, she has to come up with a constructive way to deal with Connie's insubordination, without going to management herself (until it is to recommend Connie's dismissal, backed up by poor written reviews, write-ups/disciplinary action, and iron-clad evidence of her sabotaging/lying). If she is currently being ignored, perhaps she could begin documenting Connie's actions and try again. I know you dont want to leave her in the dust on this one, but you 'sticking up' for her in this case is not
the same as her advocating for you professionally (IMO, with my limited knowledge of the situation). As far as how you dealt with Sandy, it was very professional, and EXACTLY what you should have done. SANDY now needs to speak with Maggie about Connie's behavior, and it needs to escalate from there. By getting involved, you will only damage your reputation, and you wont lend Maggie any credibility (as a professional or as a manager) by your actions either, especially if management has already considered firing everyone because of the bickering, you would only be entering the fray, in their opinion.
I spent time arguing with Sandy yesterday that I should have been spending on work that was scheduled ahead of time.
That being said, it looks like you have clearly made up your mind to say something, and if so, I think you should use the above quote as your angle. It is very difficult to tell you who to go to and what to say, because, really, this situation doesn’t involve you directly, other than a co-worker pressuring you to work on a project that you clearly stated that you did not have time for. You could theoretically address Connie’s lies about using you as an editor, but I wouldn’t unless you have written proof that she has done that (which you mentioned in a previous post, which was the correct and professional way to go about it).
Go to the appropriate person and tell him/her that your time is being invaded upon by others in your department and that you would like to focus your work to be the most efficient possible, but if you keep being interrupted, that wont be possible. Could the [appropriate person] please speak with the team to ensure that everyone understands their respective roles and what the duties of those roles are.
That’s about all you can realistically do. My guess is that they are going to see it as you ‘entering the fray.’ and as Maggie not being able to handle her superior position.
I hope it works out for you. Let us know what happens.