We have a similar situation for several of our product lines, and to get around this we:
Provide a single up-front bot and messenger deployment. This handles all of the un-gated content as well as a path in the bot to authenticate. Similar to your screenshot, we ask the visitor for their email or phone number, then within the bot we do a data action (API call) to Salesforce or other platforms. If we find this email or phone, we ask the visitor to validate something about their account (like a PIN), and if successful we transfer them from one bot to another bot flow - and this second bot flow is not tied to a messenger deployment, you can only get there after getting through the gate of the first bot. This second bot has the same general and ungated knowledge, and all of the private info linked to the logged in user.
The way I've understood Authenticated messaging from the Genesys design, is that you're supposed to stash it behind a website login - IE someone logs into their account on your website, and then they access authenticated messaging deployment. Their take is a very niche and specific setup, that does not seem to work for many of us in the user base.
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Brad Murlin
Zillow, Inc.
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