From personal experience, if you don't have any children, I find doctors hesitant to perform a hysterectomy, even though your case sounds pretty severe (like mine). I would skip the OB and visit the RE, honestly. The RE should be able to tell you if they think a collaboration with an OB may be necessary.

I don't see an OB specifically, either tbh, so I don't think it's required, necessarily.
I think an RE would be better suited to your needs since you have PCOS anyhow. OB's aren't typically well versed in how to treat PCOS.

I hope this has been a little bit helpful to you!