Can we consider any core Buddhist teaching as dogma?
"A principle incontrovertibly true" is not a dogma. E.g. in math the principle of associativity -- a + (b + c) = (a + b) + c -- is incontrovertibly true, so what? A principle must be "incontrovertibly true" within some domain -- otherwise it would be useless.

Instead, dogma is a thesis to be taken on blind faith, with no logical proof nor practical evidence. Another definition of dogma is a thesis mistakenly absolutized outside of domain where it is legitimately valid.

As any science, Buddhism -- the science of Liberation -- has its principles, its truths. And within the context of Buddhism they better be true -- otherwise we'd have to throw them away!

But yeah, we have to be careful not to take Buddhist truths as dogmas. Which means two things: 1) by all means try and map what it really means that e.g. "the origin of dukkha is craving" onto one's direct experience; and 2) not unwittingly absolutize e.g. the celibacy precept for monks to mean that procreation in general is bad.