Function of the sentence final particle こと in this sentence?

Question

I am wondering what is the correct way to interpret the こと in this sentence: >どこかへお花見に行きませんこと。 It is an example sentence found in the book "All About Particles" (page 120). It's described as being basically an alternative way to entice/invite someone to do something together. If that's true, how does　こと change the meaning and feeling of the sentence, especially when compared to: >どこかへお花見に行きませんか。 >どこかへお花見に行きましょう。

Answer 1

どこかへお花見に行きませんこと。means どこかへお花見に行きませんか: Would you like to go to see the cherry blossoms somewhere? >どこかへお花見に行きましょう。Let's go to cherry blossom viewing somewhere.

行きませんこと：　This ことis used in lady's spoken Words at the end of the sentence to be elegant. These lady's words are called, お嬢様言葉の「ことのて言葉」、which is 「～こと」, 「～の」、「～て」are used in the end of the sentence in lady's speech. It is ultimate humble language.

Answer 2

It looks like it might be derived from a written expression used as an imperative of to give a feeling that something should be done. To be honest I don't think I've ever seen it, so it may be outdated as well.