Answered How to get all resources linked to current

The only way resources are related in MODX is by parent/child relations in the resource tree. If you can make the resources children of the Financing Organization pages, it gets very easy, though I can see why that might not be possible if there's a many-to-many relationship between projects and financing organizations. In that case, the best solution would be a custom DB table where each record lists the resource ID of a project page and the resource ID of an associated financing organization. This would mean developing a custom infrastructure to manage the table and produce the output. It's probably not worth it unless the site has a very large number of projects and financing organizations.

The TV thing will work, but it may be somewhat slow. If there is a resource field you're not using (introtext, description, longtitle, menutitle, link_attributes, etc.) you could put the list there and use the &where property of getResources to grab the pages you want, but be careful about the length of each field.