sorry, I looked at it too quickly and thought it had something to do with tefilas haderech (it does mention tefilas haderech in front, but it just meant that you say tefilas haderech there or something).
As DY already pointed out, nusach Ashkenaz doesn’t have that phrase. That’s why I never heard of it before and also why I thought it was part of tefilas haderech. I have never said it and never even heard of it. But if it’s part of nusach sefard, then many Jews do say it every day, so you’re right in terms of the point you were making (even if your words were inadvertently inaccurate).
I didn’t realize that there’s a “comma” in between alila and misa meshuna. That mistake was probably at least partially based on the fact that I thought this was tefilas haderech.
“Dying al kiddush Hashem doesn’t require a nisayon or even a misah meshunah (I guess depending on how you define misah meshunah)”
I had thought of that, but then decided it wasn’t a good argument since wouldn’t any death al Kiddush Hashem be a misah meshuna. Although, as you point out, I suppose this depends on the definition of misha meshunah. I would assume, though, that any unnatural death would fall in that category.
I still think that my first argument that it might be excluding a misah meshuna that is al kiddush Hashem is a reasonable argument. Most misah meshuna’s are not al Kiddush Hashem. We don’t want to die a misah meshuna that does not have the purpose of being a Kiddush Hashem.