No this is not possible the panel can only connect to one frame at a time.
You can use RossTalk to send messages via Custom Controls to trigger the other Carbonite.
Keep in mind that when you connect the first Carbonite into the second carbonite it is going to be 1 line after the second carbonite. That means all sources in the first Carbonite are going to Drop a line unless you add a frame sync to the input on the second carbonite that is from the first carbonite. That will make them aligned vertically but now that system/sources will be 1 frame delayed relative to the sources in the second switcher.
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Les O'Reilly
Director - Switcher Product Management
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