I think the last time you came here, someone already told you that you can't take care of the communication between the guys. This advice hasn't changed. Stop going in between them and just put your foot down, tell that this isn't working for you and schedule some weekly talk-time for the two alone. If they aren't able to look after your needs and theirs, they need to put some extra time on the line to work on their shortcomings.
I know that it's hard to make yourself a top priority, especially if you feel like you are 'doing something' to them by 'making' them be in such a relationship with you. I have had my share of those feelings as well. But this won't work if you don't stand up for your needs.
As far as I see it, you know where and what the problems are, so go tell them that you want this situation changed and solved sooner than later. If they aren't able to behave appropriately you have to and take the lead. Get them at a table and if they don't want to, let them face the consequences and withdraw yourself for a while. That's what I would do. I can't do more than tell them what I want and need. If they don't care about that - their loss.
Facts: 30, female, bi, v-type relationship with Sward (husband, straight, mono) and Lin (boyfriend, straight, mono), poly-fi and co-primary.