Particularly problematic is Rabbi Schneerson's statement that they question, "Why create a fossil?" is no more valid than the question, "Why create an atom?" This is a strange statement; a fossil is directly misleading in a way that an atom is not. Asking why create an atom" is a pointless philosophical speculation, but asking "why create a fossil which appears to be a dead dinosaur if no such creature ever lived" is a very reasonable and obvious question." (page 159).
While I do believe that we can suggest theologically coherent reasons why the world would have apparent age I don't think from the standpoint of Jewish tradition we can be so bold as to demand one:
Accepting the Creation [as opposed to Aristotle's theory on the Eternity of the Universe], we find that miracles are possible, that Revelation is possible, and that every difficulty in this question is removed. We might be asked, Why has God inspired a certain person and not another? why has He revealed the Law to one particular nation, and at one particular time? why has He commanded this, and forbidden that? why has He shown through a prophet certain miracles? what is the object of these laws? and why has He not made the commandments and the prohibitions part of our nature, if it was His object that we should live in accordance with them? We answer to all these questions: He willed it so; or, His wisdom decided so. Just as He created the world according to His will, at a certain time, in a certain form, and upon a peculiar time, so we do not know why His will or wisdom determined any of the things mentioned in the preceding question. But if we assume that the Universe has the present form as the result of fixed laws, there is occasion for the above questions; and these could only be answered in an objectionable way, implying denial and rejection of the Biblical texts, the correctness of which no intelligent person doubts. (Guide for the Perplexed, 2:25, Friedlander page 199-200).I've looked over the larger context and the Rambam's line of reasoning isn't entirely clear to me. Specifically while I think this passage is clearly and directly relevant to our topic it seems a little ambiguous why the Rambam seems to accept that such questions would be relevant given a different set of assumptions.
I believe he is saying that given the general presumption of the Biblical account of Divine Creation which allows for the supernatural all of these questions are an issue of Divine Will, which we may or may not be privy too. Conversely (as I understand it) it is not that accepting Aristotle's position which demands we "disbelieve all miracles and signs" gives us justification for asking these questions, which in turn must be "answered in an objectionable way". Rather the questions are merely rhetorical, the objectionable answers being that such things are simply not possible [in Aristotle's worldview].
At any rate, the Rambam gives a strong indication that our inability to know God's reasoning for an action is of little consequence. This is so even though I believe he does attempt to answer some of the very questions he mentions.