But this is assuming what you are trying to prove!

And I don't think it's a question with an obvious answer.

Consider Newton's Law of Universal Gravitation. Planets and stars were just as bound by it before Newton as after. It's hard to think of Newton "inventing" it - he discovered it.

But the law of gravitation is a numerical law.

If you had one more or one less chromosome, your life would be dramatically different even if you had no idea that numbers existed.

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Also, the idea that mathematics is invented has some serious practical objections.

If people all over the world were independently inventing a map of some imaginary continent, you would expect dramatic inconsistencies between them, particularly before international communications were a thing.

Yet mathematics has been independently "reinvented" several times and the same truths "reinvented" by people who had no idea of each other's existence.

The Greeks and the Arabs went about mathematics in diametrically opposite ways, the Greeks being more geometric, the Arabs more numeric, and yet they ended up with the same set of truths.

Surely this points to math as being discovered and not invented?

In contrast to this, theologians and priests have gone about "discovering" religion, and I would say that there is little or no consistency from place to place there! This lack of consistency would be exactly what you would expect of a subject matter that is invented and not discovered.