They didn’t generally refer to it explicitly as epigenetics - they tended to cover the exact mechanisms. Check out pg 358’s dedicated subsection to methylation, for example. The word epigenetics won’t be mentioned, but it’s one of the classic epigenetic mechanisms.

I'm not sure if I understand that section correctly, but it sounds like it's talking not about inheritance across organisms, but about replication within an organism?

Methylation and acetylation of sex chromosomes is inherited. In somatic tissues it affects downstream development; in gonads, it becomes a heritable trait.