If They Are Seers, Where Are The Revelations?

Please help me understand: The church claims the Q15 are prophets, seers, and revelators. The Book of Mormon teaches that "a seer can know of things which are past, and also of things which are to come, and by them shall all things be revealed, or, rather, shall secret things be made manifest, and hidden things shall come to light, and things which are not known shall be made known by them, and also things shall be made known by them which otherwise could not be known." (Mosiah 8:17).

There are a number of historical issues/questions that cause many to leave the church (e.g. why are do the Book of Abraham "explanations" or translations not match anything known about Ancient Egyptian?). In many cases The church does not provide answers to these issues, but apologists attempt to make sense of it (e.g. well... we don't know what Joseph was thinking... he may not have been "translating" but instead was probably creating a modern interpretation or interpreting the facsimiles in a way that a Hebrew would have...). If the Q15 are seers and are able to know of things that are past by revelation, why haven't they? Why don't they answer the questions? I mean that question totally sincerely. People regularly asked Joseph Smith to provide revelations for their questions and he provided one. If they have such powers, why not settle all of these historical questions and tell us how it all happened?

(I know the non-believer answer here, I sincerely want to know from a believing perspective why these prophets, seers, and revelators would not reveal these things. And "it's not necessary to our salvation" doesn't seem to answer the question because plenty of non-essential things have been revealed.)