Maybe you can establish some boundries with these people.

It is ABSOLUTELY UNFAIR to put you in the middle like that. I can see how from their point of view they may think it is the only way to get the information they seek but you may have to put your foot down if you can. "Listen I'm not going to be the go-between for you two, you are both my friends and I won't be a stool pidgeon on her actions for you just as I won't be a stool pidgeon on your actions for her. If you two have issues involving your child, you two have to work it out yourselves like adults. That is the only thing that is fair for you and for the baby."

Or maybe when one asks for information, give them the other's phone number (although I am sure they already have it) and maybe they will get the hint.

You should not have to give up your right to be friends with them and get the support they have to offer for you just because they are acting immaturely with regard to each other.

It is not your responsibility, so don't eat yourself up over it.

Good luck, I know it is a difficult situation.