First things first, there seems to be a typo in your quoted text. I googled and found a source with the correct version:
So the part you extracted seems to be a subordinate clause that's connected to the following line.
I can't find a duplicate target specifically on なお to point you to, so I am going to make an attempt at an answer. Surprised this seemingly hasn't been asked before.
an adverb that indicates that an action or state is still going on or the degree of something increases; a conjunction indicating that an additional comment follows what has just been said in the preceding sentence (source: A Dictionary of Advanced Japanese Grammar, Seiichi Makino, Michio Tsutsui, Japan Times, 2008)
The meanings that なお effects include: "still", "even more", "all the more", "additional" or "additionally", "and", "furthermore". Here it is used to describe an intensified degree, and this usage often occurs with a verb or an adjective.
Another grammar point that might be worth mentioning—although you didn't ask about it in your question—is ～ようが、～ようが. It's verb volitional form + が／と／とも. These occur either in pairs or alone. This phrase has a pretty big variety of different forms. It can be used with verbs/nouns/形容動詞/形容詞, but since you seem to have gotten the general idea, I won't get into detail on that. The meaning is as you say, "even if", or "doesn't matter if", namely, what's stated after it is true despite all the things being stated in the ようが phrase.
ってこと ＝ ということ
どんなことなのか with a question/unknown marker か and an explanatory or explanation-begging の
For のか please see this answer
The part you are asking about roughly means:
Humans, weak just like you've said, even if mangled, even if stabbed, still go on living regardless. You know what that's like? You should get a taste of that!