@Shay1018,
Let's operate under the assumption nothing untoward is going on.
Your husband has to accept your daughter growing up. And at puberty, she's going to want her privacy. As in, if her period starts, it hurts like hell and she accidentally soils the sheets, I would bet dollars to doughnuts that she wouldn't want him to be there to witness all of that.
So talk to your daughter (because this affects her, too). She probably also wants the co-sleeping to end, but doesn't feel she can say so. And if she doesn't want it to end, then maybe use the example I've just given. It is
inevitable that she will want her privacy at some point during her teen years. That's about as sure a bet as anything can possibly be.
Then talk to your husband again. If he claims your daughter isn't saying anything, make it clear that the two of them are far from equal in stature and she didn't feel should could or should say anything. Don't let him put her on the spot because that's a pretty sure way to get her to clam up. And then he'll continue to think that he's right.
His "you can't tell me what to do" nonsense is just that -- nonsense. Of course you can tell him. It doesn't mean he'll listen. But you're more than entitled to speak your piece. And him ignoring your feelings is rather different sort of red flag. If he ignores your feelings for this, does he ignore them under any other circumstances? That's not the recipe for a happy relationship.
Anyway, to bring it all full circle: there are a lot of guys who don't accept their daughters growing up, and that may be a big part of this. I had to let my own father walk in on me in my bra to get him to quit just opening up my bedroom door whenever he felt like it, claiming it was his house and he could walk around wherever he liked. I was around your daughter's age IIRC.
Hang in there. Even if everything is awesome, the co-sleeping has to end eventually. This is likely a very good time for that to happen.