We use Zammad for internal Ticket tracking also in some cases where we do not want external customers to be able to open tickets for.
Could you add an option to groups that set them internal or public?
So if a customer tries to open a new ticket via the web interface only public groups are shown and internal are not?
Internal groups would then only show for Agents or higher.
if i got you right that’s already possible.
Have a look at Admin - Channels - Web. Only the groups selected there are available for customers. Any agent can still see all the other groups (depending on their roles).