@Muiren, I feel your pain. You’re in trouble here for two reasons:
Reason 1: technical
From a UX perspective, separating a community web site from its discussion system is an aberration. In a bright future, web sites and discussion platforms will be accessible as components, which you can mix together to design an integrated experience. But we are far from this at the moment. Your web site is probably a monolithic pile of spaghetti code (did I hear Wordpress?) and Discourse is a monolithic platform.
You are suggesting using iframes to combine them. It is technically possible. In fact, lately, I have spent quite some time doing precisely this. But, like others have mentioned, it is very difficult, because iframes have not been designed for that purpose.
Reason 2: political
People here won’t help you with this. Possible reasons are:
- They see no possible positive outcome (because of the technical challenge I’ve mentioned) and think it’s a waste of time.
- They have “made a virtue of necessity” and will defend the monolithic approach.
- Discourse is a commercial product whose source code is open. To charm “serious customers” despite the “open source” label, Discourse marketing strategy is to promote an “opiniated” approach. A direct consequence is that alternative use and experimentation are discouraged.