Thank you for your suggestions. I will look into building a sample for you of this project. Also we have verified the file path is correct. In addition, we have done some debugging into this issue. We found the issue occurs both locally and on our server due to how we are impersonating the forms.
Our lead web developer said, "If we change the application pool in IIS, to use our impersonation account as the Identity for the Application Pool, it all works. However, we don't want to use our impersonation account for the whole website as it has access to network resources."
Currently we are Impersonating the needed forms individually in the Web.config such as:
> <location path="Forms/GISToolbox/GISReporting">
> <identity impersonate="true" userName="userName" password="password" />
Whenever we do this we can access and verify the path exists for the shapefiles in our forms. Consequently it seems the dlls are not within the scope of the impersonation and hence not able to verify the shapefiles filepath exists (Screenshot of the file does not exist error over the map: https://www.screencast.com/t/RyJTqUeLu).
Do you have a suggestion to use impersonation for individual forms that will work within the scope of the dlls?