ほとんど / しなくたって

Hi,

1. 私たちは遠征試合でほとんど負けた。

This is translated as "We lost almost all our away games". I read it as meaning that they almost lost one particular away game. Where does the "almost all" meaning come from?

2. 「君が何でもかんでも自分のせいにしなくたって」

What is しなくたって? I suppose it is something to do with しない, but I don't understand the ending.

1)
"Almost lost a game" is （ほとんど）負けそうだった/負けるところだった. 負けた means "lost", whereas "almost lost" is actually "won".

2)
～たって is conditional, similar to ～ても.
しなくたって ＝ しなくても（いいのに）

ほとんど is usually used in the "almost always"/"almost all" or "almost never"/"almost none" sense so it really doesn't apply to one instance. Even Toritoribe-san's example about one game reads like it's talking about multiple things e.g. moments in time. I read it like "It looked like we would lose almost the entire time." Without the ほとんど it doesn't have that nuance.