Since all the Baltic states and Poland are now part of the Schengen Area, Estonia has a contiguous connection to the rest of the EU. Is there a single continuous highway or high-speed rail between Estonia to the rest of the EU through Poland that can be used for land travel?
Simply put: no, there is no such road (expressway or motorway) nor high-speed rail through Poland in that direction
Why do you ask for "continuous" one?
The understanding of the world "highway" differs from culture to culture. There is the E67, is that enough for you or are you asking for a more substantial road?