Scientific consensus isn't "we believe"; it's "the results of widespread, independent, carefully executed, controlled experiments show."
Further, it doesn't mean that it "must be true" but rather that it is more likely to true.
Further, it doesn't mean that it "must be true" but rather that it is more likely to true.
The fact that cosmologists don't perform laboratory experiments with miniature black holes doesn't reduce the scientific standing of cosmology, as long as there are equally persuasive sources of evidence to support the theories.