Question about use of "sore" in paragraph

A butler is being interviewed by police; his former employer has been murdered.

「わたしはあの事件で旦那様が亡くなられたことを知りました。それでもわたしは何もしなかった。旦那様がそれを望まれたのにも関わらず。」

"I know the master lost his life in the incident. But I did nothing. Even though..."

Did the master want the butler to "do something"/intervene or not? I'm having trouble determining what the "sore" represents. I would guess the "nani mo shinakatta", meaning he did not want the butler to intervene, but the "ni mo kakawarazu" doesn't make much sense in that case.

Thank you for any help.

旦那様がそれを望まれたの(を知っていた)にも関わらず、わたしは何もしなかった。
Even though (I knew that) the master want IT, I did nothing.

But I can't understand what IT means in this paragraph only.
BTW, I guess maybe IT means "villain's death" or "to avenge on the villain", but the master didn't want someone especially the butler to do something.

The "sore" isn't referring to the 何もしなかった, the fact that the butler didn't intervene, correct? That's my main point of confusion.

Oh, sorry, I can't understand yours well.

Yes, それ have no relation to 何もしなかった.
BTW, それでも means simply "but" as you translated, so I think your question is about それを.

The master wanted IT, and the butler know that(, but the master didn't order him to do IT).
After the master dead, the butler thought "if I do IT, the master will be pleased in the heaven", but he didn't do IT.

Excuse my poor English...
I hope this can be of any help to you.

Blenheim,

わたしはあの事件で旦那様が亡くなられたことを知りました。それでもわたしは何もしなかった。旦那様がそれを望まれたのにも関わらず。」

"I learned that master lost his life in the incident (accident?). Yet, I did nothing. Even though master wished me to (do something)."

...is the natural way to interpret it.

These kind of expressions are often confusing, especially when they're colloquial. You just have to guess from the context sometimes. But do check more context. You never know what is hidden in the next sentence or so, or even the ones before.

By the way, after reading Uco's post,
I noticed that 旦那様がそれを望まれた matches "the master ordered me to do IT (expressly or tacitly)" well.
If it's 旦那様がそれを望まれていた, maybe it matches "the master wished IT(, but the master didn't order him to do IT)" as my version.
Although it's a subtle nuance.
Sorry to be confused.