Ok, I thought the scope of your topic was much broader than that. (For example I have had mixed success in getting participation by @-mentioning local observers on a journal post for a project.)
Since this is a forum specific question I moved it to the forum category.
There are four innuendos regarding the target environment:
If an event/project can be organized via the tools of inaturalist.org
If an event/project can be organized via the tools of iNatForum
How an event/project can be organized via the tools of inaturalist.org
How an event/project can be organized via the tools of iNatForum
And within the body of the OP, there were also invitations to two target demographics; one being prior event/project organizers and the other being members who may be wanting to participate in events/projects.
And please keep in mind I just joined this site a couple weeks ago and still trying to understand the ecosystem by studying the available material and asking questions.
I may have made an incorrect assumption that inaturalist.org and iNatForum are symbiotic structures. Perhaps they are independent in governance, and only share user names and logins as a commonality.