Currently Spotfire is limited to supporting 1 spatial geometry when using maps. I was able to configure 2 geometry objects into my infolink, and both appear/render in a table visualization. Unfortunately when you try to map both columns separately, it defaults to the first only and there is no way to specify which column in the layer settings.
Ideally, you could explicitly state the geometry column to be mapped in a feature layer. This would allow one table to support multiple mapping layers.
Unpivoting the data is an option, but it was not preferred in my use case as the table acts as a 1 row per entity style table.