OBTP on Cisco Roomkit works fine adding a MSTeams link in the Google Calendar Event but as of now , the MS teams add-on in Google calendar for showing OBTP is not supported scenario for webex hybrid calendar.
Google Calendar with MSTeams addon
Create an event adding MSTeams Videoconf and Room with a Cisco Roomkit (the addon create the link in the specifiec field of event, not in the description!)
At the correct time, the roomkit shoud have the OBTP for "join call" (using the WebRTC integration).
Today, MS teams add-on provides the joining link in a from that Webex cloud does not recognize. Due to that Hybrid Calendar does not find the MS teams meeting and add OBTP