Drupal views - 2 latest reports and related content
You can create view in a view using View Field View (https://drupal.org/project/views_field_view):


Create a view of reports
Create a view of amendments which takes a contextual filter of node id and filters amendments which have a field reference with that node id value
Put the view amendments view in a view of reports as a field (using above mentioned module - see it's documentation for more specific info if necessary)


Btw. just a thought - isn't it possible for you to switch the architecture and have the node reference field in the document content type, referencing the amendments? - this way you wouldn't need a view in a view and it would be easier to display it.