How can we post events or resources anonymously - or as a group?

Create a Capacity4Dev profile as your DEAR project! 

See the DEAR Support Team as an example. 

You can share the login and password and coordinate among selected "writers". 

Then you post as a project, rather than as an individual. 

This is also good for project sustainability - in case new people take the role to share information on Capacity4Dev. 

The disadvantage: it is less personal and requires a bit more coordination.