How can I disable the messenger on a particular page?

I'm using a Squarespace site and have the code inserted on the Code Injector section of the main site settings so the messenger appears site-wide.

We have a couple of internal (password protected) pages that we're using for reporting to our clients, but want to disable the messenger on those pages only. Is this possible?

I looked at installing the Google Tag Manager, but am worried that this would interfere with other tags installed on the site (it's a microsite for a larger entity).

Thanks!