Hi Nina,
Thank you for the detailed steps.
The only workaround I see go to Security configuration under the System Admin module.
Select the Role for which you want to hide the form.
See the below example. I want to hide Loan items form

Go to Security configuration

You can only give access based on your requirement.

Once done then publish the changes.
Login with desired role and check the form again.

Note: Before doing this, please duplicate the role and make the changes accordingly.
I hope this helps.