"Miracles" wouldn't be evidence of the divine unless science was, in principle and permanently, incapable of explaining them. If the laws of physics were changed or ignored in order to perform some feat which was explicitly an attempt to prove the existence of the divine, then sure. If, however, a long-dead person were to spring from the grave and perform a jig, scientists would be (to borrow from the vulgar vernacular) "all over that shit". Even so, the mere existence of permanently inexplicable phenomena is evidence only of the strangeness of the universe, and not of a conscious omnimpotence behind it.

I don't disagree.

I might be mistaken about the use of the word "plausible", but I think it is not necessarily connected with evidence but with human perception. Of course rational people would only find plausible explanations that are backed with evidence, but even the most hardcore rationalists are subject to their own psychology and emotions.

My argument is that in a (completely unlike, hypothetical) scenario like the one I describe, most people would likely find plausible what that someone would claim (if it did not sound completely stupid) not because it would be the reasonable thing to do but because psychologically those acts would feel too imposing, if science could not explain them at the time.

If those miracles occurred and were scientifically verifiable as you say, then they become part of science, not religion. Certainly it may throw a lot of existing science into doubt, but that's what science is all about. If we can test and verify those miracles then they aren't religion anymore, and the people who are going to provide the explanations for how the miracles work and what they can do won't be priests, they'll be scientists.