In the Event Viewer, try searching for EoCApp.exe.
The crash reports are sent directly to the programmers, and are reviewed when preparing new game updates.
CrashDump files are (usually) created in the install folder '..\SteamApps\common\Divinity Original Sin 2\DefEd\bin'. Zip a few together, along with the gold.log file in the same folder, and email it to supportdos2@larian.com. Alternately, you can email / post / PM a Dropbox or Google drive link, etc.
Did you try a lower FPS cap, such as 60?
Did any of the troubleshooting (lower graphics settings, windowed mode, a clean boot, etc) seem to affect the frequency of the crashes?
