Here is a suggestion to see how well it might work.

Could you create a new category for your new bulletin board that would be exclusively for Earthquake Forecasters?

It might have a heading such as “Earthquake Forecasters Only”

The posts would be visible and readable by any site visitors. But only people who were actively involved with earthquake forecasting work would be able to post notes to that section. Other board posters including Roger could send those people E-mails in response to their posts if those people allowed that. But they (including Roger) wouldn’t be able to post notes in that category themselves.

This is necessary because except for me, perhaps, Earthquake Forecasters in general won’t tolerate any criticism of their forecast information. If they are criticized too much they will just stop posting.

If you don’t want to create such a restricted category or it just doesn’t work then I will likely eventually create such a resource on my own Web site. But again, I just don’t have time to monitor a bulletin board myself.

People might complain that this is a restriction on their posting ability. But the board itself represents a restriction on people's posting abilities. This new category would just represent a more restricted posting board within an already restricted posting board.