Unfortunately text elements within a DWG or DGN are not exposed in the Revit API (and therefore Dynamo), which means there is no way to access them. The only option is to explode them using the standard Revit Explode command, then you can filter these elements using Dynamo. I believe there is a way to do this using the RevitAPIUI, which simply automates the explode command (see link), however its limited to Revits 10000 element limit.
@jacob.small suggestion is worth pursuing if you are an AutoCAD user.
I’m going to be looking at adding text conversion functionality to BimorphNodes when I find the time as there is another method I am aware of that utilises DXF