If you want attendees to have the ability to interact with the SME's I would recommend using Webex Meetings. You can either have the SME's in the main room and available for discussions with attendees as they come into the meeting or use the Breakout Rooms to place SME's in a separate room and as employees join the meeting the host in the main room can move them to the appropriate break out room. If you use breakout rooms, make sure you check your permissions for attendees to leave and rejoin break out rooms as well as set the timer for how long the breakout room should remain open.
