jmh:
I think he was going for a more philosophical answer, but I think his point remains valid. Also, I don’t think your point of logic vs. revelation is relevant here. Logic is not fact, it is a tool of reasoning- meaning because something seems logical doesn’t mean that it is necessarily true, just that given a number of facts and a certain amount of understanding, we can assume a conclusion.
But in this case, the argument is that scientists don’t have all the facts, be it because of changes in nature or previous universes etc. That is not an attack on the logical conclusion of scientists, but a statement towards the accuracy of the currently observable data to conclude the reality.
In such a case, if someone with complete knowledge of the relevant data – not just the observable, were to reveal to me the purpose these bones, it should take precedence over sciences conclusions.
Just for example take some rain-forest tribesman’s logical conclusion of the purpose of a chair vs. a civilized individual explaining to him its purpose. The tribesman might be very logical but his conclusion will still be faulty.
Also, I don’t think the chumash explicitly says how old the world is but chazal does.