I assume you have setup many-to-many relationships between post type "submission" and "requirements", and you are going to connect each "submission" post with multiple "requirements" posts in front-end with Toolset form plugin.
If it is, you can try these:
1) Setup many-to-many relationship between post type "submission" and "requirements", for example the relationship slug is "submission-requirement"
2) Setup some posts in post type "submission" and "requirements", leave the posts relationship empty, this is required, since the relationship form works only for existed posts, within Toolset post form, you can not setup the relationship directly when create/edit a "submission" post. In this case, we need to use relationship form to setup the many-to-many relationship "submission-requirement".
3) Dashboard-> Toolset-> Relationship Forms Editor,
Create a relationship form with Toolset form plugin, for example "Setting up a relational post form", see screenshot relationship-form.JPG, you will need to customize it according to your own website settings.
4) In a single "submission" post, show above relationship form for assessor(or some specific) users
for example:
[cred-relationship-form form='setting-up-a-relational-post-form' parent_item='$current']
See screenshot relationship-form2.JPG
Test a single "submission" post in front-end, you should be able to see the relationship form "Setting up a relational post form", with it assessor(or some specific) users can connect this document post to multiple "requirements" posts
5) And In a single "submission" post, you can create a post view, query "requirements" posts, filter by the relationship "submission-requirement", and display the "requirements" post information.
More help:
https://toolset.com/documentation/post-relationships/how-to-display-related-posts-with-toolset/#displaying-many-related-items
Hope it is clear.