For your multiparty meetings, you will need to dial the Webex Board and the Poly (formerly Polycom) endpoint in to a Webex Space instead of doing a 1:1 call between the endpoint and the WxB.
If you do it that way, then the Poly endpoints should also be able to see the whiteboard as a content stream (as a view only content as they don't have the ability to interact with it).
Alternately, with the latest software versions on the WxB (ie CE9.8.0), you could register your endpoints to your local on-prem call control, in which case, you can use any local Muiltiparty capabilities (such as Cisco Meeting Server) to host your meetings on-prem. See "Support for Cisco Webex Board on-premises deployment" section in the CE Software Release Notes.
Wayne
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