No the keyers can not Move from the MEs to the MiniMEs.
if you don't need a Keyer to "cross miniME tile boundaries" then you can "drop" down from Canvas control layer to MiniME layer and then put Key 1 of one MiniME in it's region with a source then go to another MiniME and use Key 1 again. The moment you touch Key 1 at the Canvas layer it will pull them back together.
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Les O'Reilly
Director - Switcher Product Management
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