Didn't we discuss this concept before? It looks very familiar and I'd hate to take you back through ancient history here.
This looks like something to handle with a join table and a many to many relationship. Fields defined in the join table can document the status and other details specific to this pairing of a company and a prospective partner. Then your notes field can be replaced with a portal to this join table.
Ah, the join table, you're right! How come you always answer me ... did they assign you to handle all the idiots? :-)
BTW, you can edit your original post to add a screen shot instead of posting a separate unconnected link: Join Table, a little more help?
This will take the same basic set up like you already have for Projects 2----<Project_Company>----Company 2
The layout above would be based on Projects 2 instead of Projects (respecify your fields on the above layout to be from Projects 2 instead of projects.) and add fields to Project Company to document the status of each prorspective partner. Then your portal can be a portal to Project_Company.