based on that info i conclude that it probably broke.
Could you compare the exported files in the output folder with ones that appear in temp folder next to the application after pressing Run (closing the game clears them).
There’s no difference between running a preview and making an exe, except where files are wtitten to. Perhaps something prevents access to where you’re exporting to (windows, itchio app, etc), or there’s path abnormalities (non-latin characters?).