Hi,
I saw that last commit in this repo (https://github.com/SIWECOS/HSHS-DOMXSS-Scanner) was some time ago.
there are well maintained tools like mozilla observatory (https://github.com/mozilla/http-observatory) or securityheaders (https://github.com/securityheaders).
Have you been thinking about using one of them as they might contain new headers that are not contained in your old scanner?
Greetings
Joejoe2010