Ivan,
You are overthinking this. It�s easy.
Report link fields just love to run reports. They just need two values to match on.
So just coax the Record ID# of the Company down to any child table in your app, or grand child, or great grand child.
Then on the Company table create a Report Link field and on the left field in field Properties Select the Record ID# of the project and then on the right side of the configuration in field properties navigate to your app and the target table and locate the Record ID# of the project to match on.
Then just put that report link field on your form and set the form properties to display the children directly on the form and probably build a report to use for that purpose. Sent the form to use that report.
