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Would any of the VIs in \vi.lib\Utility\VariantDataType\VariantType.lvlib help you? You should at least be able to use the GetTypeInfo VI to see what your mystery F1 is.

The Variant To Data function can do this. Wire in an array of variants into the type input and a variant representing your cluster into the variant input. See the attached image. This also lets you go from a variant containing an array to an array of variants.