Hi Emma,
Without looking at the exact session setup it is a bit hard to give an exact resolution on this. But as you mentioned if you are using your own zoom setting having multiple speakers on the screen at the same time it should be possible using the Multi - Speaker view within Zoom.
Once the meeting is live.
Click the View option on the top right > Choose Multi-Speaker option.
I have also added a screenshot for the same. Let me know if this solution helps.
This way both speakers should be present on the screen at the same time during live stream. Also, in case you want, going forward you can use Cvent own Attendee Hub Solutions to have a better customization options during the live streams with our Studio options.
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Anurag Sindhu
Senior Client Success Advisor
nonea
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