Hello Daniel -
My apologies that this reply is coming so long after you posted your question.
In case you are still facing a workflow in which a GeoTagger processor (out-of-the-box) is producing a list of GeoFences which satisfy the spatial criteria (e.g. GeoEvent Geometry INTERSECTS .*/.*) when GeoFence areas overlap, please take a look at the custom processor below which has been uploaded to the product gallery:
This custom processor is intended to be placed in-line with a GeoTagger, immediately following the GeoTagger, to split a single GeoEvent whose GeoTags attribute field contains a list of values into multiple events. This should eliminate the need to incorporate multiple Field Calculator processors in your GeoEvent Service to manually pull the names of GeoFences out of the list by hard-coded index.
Please let us know how this custom processor works for you.
Best Regards -
RJ