But it does specifically identify itself as part of Star Trek: The Fall. It doesn't say DS9 on the cover, it says The Fall. It's not hard to guess that that's the title of a miniseries. It's separate from the title Revelation and Dust, so it's clearly part of a larger whole to which RaD belongs; yet the title The Fall sounds like a reference to a specific event or process rather than an ongoing status quo, so it doesn't suggest an open-ended series. So if you see a book titled Star Trek: The Fall followed by an individual book title, it's pretty easy to deduce that it's one installment of a limited series of books focusing on a specific event.
Not necessarily. One could make the same assumption about, say, the Typhon Pact
books (which are, in fact, all more or less standalone) or the Section 31
novels (which are completely standalone), just to give two examples.
(Not taking any sides or making any judgments here, just playing devil's advocate.)