What you say would be true if we lived in a purely material, mathematical world. How can you be so sure thing's that are spiritual works the same way?
TL;DR: See the conclusion at bottom of this long post, under the word, : SO : , if you are pressed for time.
I assume you mean "things that are spiritual", the 'spirit world', which is not at all the same thing as Heaven, nor, specially, God's particular economy of operation.
I suppose I could say that if it is true in a purely material, mathematical world, then even the impinging of spiritual reality on the material world still cannot undo the fact of it, since this remains material. But this material world is (in mathematical terms) a subset of the spiritual, and not the other way around. And I can pretty confidently say that mathematical truth applies to the spirit world, just as surely as to the material world. At least, logical truth does, and logic is math-based. Now, the assumptions we make in our computations —that's another matter.
Disclaimer: When I say a thing is absolutely true, I don't necessarily mean it is 'brute fact'; I only mean it applies universally to all creation. Only God is 'brute fact'.
As I have mentioned before, we temporal beings use concepts and language to convey and organize our thought. We do indeed have a way of trusting our concepts beyond what is warranted and our words often mislead even (or maybe specially) the one who is speaking. But there are principles behind what we say, which principles we try to describe, however poorly we understand them. Mathematics is absolutely true; OUR mathematics, however, may contain some false assumptions. Pure logic is absolutely valid in any realm. Our assumptions used in logic —not so much.
So, also, in the spirit realm, cause and effect holds valid, but time passage, not necessarily. But in our logic, if we want to think time passage does not hold valid in the spirit realm, we negate it in our minds, which is in itself an assumption beyond what we can know. Maybe the best we can say is that it is likely that sequence of events does not appear the same to the spirit world as it does to us.
Hypotheticals are an odd breed. "What if" is a particularly human expression. We pride ourselves on our ability to think abstractly, not realizing how we trust the concepts we use to do so. You have heard even here on this site such logical self-contradictions as "Can God make something so big he cannot pick it up?" To me, the notion of mere chance, (and particularly easy to prove is the notion that chance can cause anything), is another equally self-contradictory abstract concept. But some people posing questions that assume causation by chance consider them absolutely valid.
: SO :
What does happen is all that does happen, here and in your 'spiritual things'. Our descriptions of them, and our playing with them abstractly in our minds —not so much. We say "what if" because we like to think our ability to abstract, is of some authority over fact. It is not. Also note, that even when God speaks to us in hypotheticals, it is usually, maybe always, in his posing to us a choice for us to make. It is not an absolute statement that either 'option' is actual.