We have webhooks set up to notify when a ticket is updated in Zendesk, but it looks like when a comment is added to a ticket, the webhook doesn't let us know whether the comment is private or public. In the screenshot you can see that the ticket was updated with a comment (and it is an internal comment), but the webhook comment_publicity field is blank. I've also tested this with public comments and that field is still blank.

Can you try updating the
{{ticket.latest_comment.public}}placeholder to{{ticket.latest_comment.is_public}}.