You can create a site that only allows them to call 911, but I feel that the Preview Mode has no trunk control like Predictive, so it may still use the user's site for dialing and if that is required, then you have to give them the ability to dial out across the board. There is no permission to restrict them from that. Now, what you could do is have a trigger for the user and watch for calls that are dialed and if it is not an outbound dialer call, then run an API that disconnects it. Essentially, you are letting them dial, but if the call is not related to a campaign, then it will not allow them to connect.
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Robert Wakefield-Carl
ttec Digital
Sr. Director - Innovation Architects
Robert.WC@ttecdigital.comhttps://www.ttecDigital.comhttps://RobertWC.Blogspot.com------------------------------