Most of the other skills are taught by traveling NPCs once you enslave them and donate them to the Goblin Houses, so that is another way you can get them! But to answer your question, yes, all skills will have a specific location where you can learn them, like mining is for the Goblin Village, Alchemy for the Heroine Alchemist, Black Magic for the Pumpkin Witch and so on (once they are implemented that is).
Monsters mostly do attacks at random, certain attacks have a higher weighing in probability to occur. Multi strike attacks generally have a lower chance to hit than single strike attacks, hence why the Werewolf missed 2/3... what sort of weapon were you using? Some weapons lower your chance to hit, such as tools, Sickles, Hammers etc, and if you dual wield them, this penalty to hit actually stacks.
Combat in general is sort of "place-holdery" at the moment and may change how it works in the future as I am not 100% happy with how it is at the moment.
Werewolf Gangbang doesn't exist yet. It's something planned for the future once the caves get implemented.