Hi Rob
Your sequence does not exist as a discrete QT file until you export it. Up to that point it is merely pointing to all of your source clips and render files where you have created effects, colour corrections, captions etc. So there is no QT file to find.
Add markers in your sequence then edit the markers to become “chapter markers”
When you export you should select your sequence and choose export, quicktime move, and you will get a window like this

If you export using current settings the quality should match your sequence quality. You can also include markers, you need to add chapter markers in FCP in order for them to translate correctly.
Finally ensure you tick the Make Movie Self Contained option.
That should produce a QT file identical to your sequence settings and quality and contain data for your chapter markers.
best wishes
Neil
http://www.patience.tv
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