So, you can cite chapter & verse where it says math must be employed to confirm a theory?
No, of course not, that's nonsense.
A theory is confirmed by, among other things, making predictions later observed as facts.
For a listing of some Darwin predictions confirmed, see this link
I can cite David Berlinski and his who is much more eloquent than I.
https://www.youtube.com/watch?v=Z6ElA0--JNg
I also like the one about the probability of a single protein falling together in an entire earth sized ocean of amino acids assuming that for some reason they'd try to fall together and at the first error they'd try again.