Hi,
the ESRI Map widget plug-in is an OEM solution that comes with Microstratgey whereas the Esri Maps for Microstrategy is a separate product in combination with an ArcGIS Online subscription plan.
You can try the new Esri Mapsor Microstrategy 2.0 with a free 60-day trial version of ArcGIS Online:
http://www.esri.com/software/arcgis/arcgisonline/evaluate
With the trial subscription activated you can download and install the solution I mentioned before.