Does data layer's file format matter to Flex?

I had a web app pulling 3 datasets from a Map Service: 2 shapefiles, 1 fGDB feature class. In the main map of the app, I was able to select (highlight) and zoom to individual features (e.g., parcels). That did not work with the file geodatabase feature class. The Search widget also did not locate/zoom to features found using the Select By Attributes.

Should the file format matter? Or, is there something else causing this issue?

Thanks,

Mike