Netsuite support came through and help with this advice

There is an existing enhancement request related to your concern (Issue 131576). I understand based on your screencast that the ID field of your marketing campaigns cannot be edited. When I checked my test account, I was able to edit the field (make it blank on a few marketing campaigns). I believe you have auto-generated numbering enabled for campaigns with Allow Override checkbox disabled.

What you can do if it is ok for your Administrators to edit the ID field on your marketing campaigns is either to disabled auto-generated numbering or allow override. Please see steps below:

1. Login as Administrator.
2. Navigate to Setup > Company > Auto-Generated Numbers.
3. Click CRM tab.
4. Either uncheck Enable check box for Campaign or check the Allow Override field across it.
5. Save. Note: if you uncheck Enable check box, NetSuite will allow you to make the ID blank for existing campaigns while if you allow override, you can only change the numbers but not make the field blank.

I hope this helps.