I have been reading various threads on reading (not writing) an ESRI file geodatabase (.gdb). What I need to do is process a feature class in a geodb and extract the vertices of each feature. I do not need a visual component as this will be just pure processing of data. Looking for an open-source framework I can readily use in my .NET project. So far I have looked at

DotSpatial: Libraries work great for shapefiles but currently no ESRI gdb support
MapWindow: Looks like it supports MSSQL, SQLLite, and Postgre geodbs but not ESRI geodbs
QGIS: Does have the capability to read ESRI geodbs but the API is currently only for Python and C++
ArcGIS: Using ArcObjects this is quite easy but would like this available for users that do not require checking out a license

What other open-source solutions would be recommended for this type of processing?