There's no moderation for fields other than image. That's something we'll be supporting in CB 3.x is to try and provide individual field moderation for every field type.

It's possible to make a bit of a workaround for this, but it's a bit of configuration work. You effectively will need 2 fields. 1 is your text field and 1 is your checkbox field. Make the checkbox field only available to moderators using CB Conditional (disable value resetting if using CB Conditional) or CB Privacy for its edit view and configure it to not display on profile. Next in your text field in its layout parameters you'd use the below to condition its display based off the checkbox fields value.

This is the manual process at least. So for example the text won't display unless the checkbox field is checked, which only moderators can do.

Some automation can then be added like resetting the checkbox to unchecked if the text field changes value using CB Auto Actions. Can also send an email using CB Auto Actions to notify moderators. I can provide examples of these if you want.

You can also create a userlist that shows all users with a value in that text field and their checkbox isn't checked so you've a nice pending approval page.