I had a deleted question (with no answer) two months ago and it could be found always in my recently deleted questions link. Today, I needed a good comment on that post but the post (the question) is missing from "recently deleted questions". Where has it gone? Is it erased forever?
The page gives links to certain deleted questions, namely those that are "recent." At some point the "recent" does not longer apply and thus the link is dropped from that list.
The question persists on the site just as before, the sole problem is to find it. The main way to do this is by preserving a direct link, via bookmarking the question.
Thus, during the period of time it was on the list you should have bookmarked it. Chances are you could still find it in your browser history, but to make things simple I'll try to give you a direct link in a comment.