I have not tested it but you could try following:
1. Create a new permission profile. Manage & settings > Permissions & Administrators > Permission profiles. Create a new with something like this:
Disable (remove the check mark) on most of the other settings.
2. Create a new administrator and assign the newly created permissions profile from step 1.
3. Open a security policy > Right click on Policy > Edit policy > Network > Drop down menu on right > Edit layer > Permissions > Select additional profiles thatt will be able to edit this layer. Select the profile we created in step 1.