Are shaving the beard, shaking hands with women, and listening to music not among the major sins, given that they were not mentioned in Al-Dhahabi's Book of Major Sins?

Shaving the beard and shaking hands with non-mahram (definition) women are not major sins, but persisting in them elevates them to the status of major sins. As for the use of musical instruments (playing and listening to string instruments, playing and listening to wind instruments, and playing and listening to drums), Ibn Hajar al-Haytami explicitly stated that these are major sins.