Aha, Negative, you identified the core of the matter:
Mmmm... try playing with the emphasis on your words:

if NOTHING did exist <---> if nothing did EXIST

This entire matter is not about something vs. nothing, it's about existence...

Saying that NOTHING exists, doesn't mean we can't be here...
Saying that nothing EXISTS, means we can't be here...
More the "nothing EXISTS"

What is nothing? A void where everything does not exist (or no thing exists there)[these are logically equivalent, if I could write the symbols for the universal quantifier and the existential quantifier]

If something (some thing) does not exist, then we cannot talk about it. [For we only know what exists, and we can only talk about what we know, how could you know something that doesn't exist? You would have to know what that thing is and you would have to know that it does not exist]

Therefore, if nothing (no thing) does exist, then we cannot talk about it.

Such that we cannot attribute non-existence to a thing only existence, but I have never run into a Purple Monkey (though if they can make mice glow in the dark, purple monkeys will probably follow soon, but that is a whole other issue), therefore I say that they don't exist, but how can I know that they don't exist somewhere (in a top secret lab, or, dundundunnnn other dimensions). Since these other dimensions do not exist in our dimension (note the stipulation), we cannot say that they do not exist.

So, even though I sort have lost track of where I was going.
It follows that we can only say "nothing" within a frame of reference, nothing can only be a comparison to something when we speak about it. However, we cannot say that "nothing EXISTS" because if it does it is not here. In addition, we also cannot say that it does not exist, because well we cannot say anything about it.

So, there is something to think about, I'm exited to see what happens with this,

Dhej