How can I grant permissions to a customer participant to access/complete a supplier performance survey (without granting unwanted permissions)?

I want my internal participants (i.e., customer company business units) to have permissions to access and complete a supplier performance survey.  However, I do not want these same participants to have any other permissions (e.g., to view supplier dashboard information, W9 information, ACH information, etc.) unless they have separately been granted such permissions as part of previous/existing responsibilities.  How can I do this?

Note:  When I add them to "Internal User" group, they are able to access and complete the supplier performance survey, but they are also able to view the supplier dashboard, W9, and ACH.

Thank you.