As I mentioned in a couple other posts - it's entirely possible to find plenty of people in academia/government/corporate life/non-profits who really like to get involved on this topic. Should this site make an effort to collect question, launch good questions, and then organize/conduct a campaign to find answers from qualified individuals? That might jump-start some interest.
Appart from the folks you attract through search (i.e. having high-quality content), your suggestion is the single best way to find and attract experts to your site!
So how do we do that?
We've all been there. Learn from our experiences:
…and a bit more apt to this specific question: