Why I am so confused as you think is because I only can find the law which states that authorized stay = I-94 duration, and I have not found the law which states that
violation of status results in unlawful presence even if the I-94 does not expire. - No, it clearly states not counted as unlawful presence in this case, in your memo.
I have not found any law stating that violation of status (with unexpired I-94) can result in removal or other penalties other than affecting EOS/COS. - Yes, it was mentioned in your memo, which is 237(a)(1)(c)(i)