So I'll take it differently. Is it possible to say that the universe "existed" in the past when there is no time? Is it time that is unnecessary here, because it is that our universe has come into existence and time has no effect on it, because it is a fact, it existed, regardless of whether the time is over? It had its own space and time, so it can not be said that despite its remains it existed? Since it exists despite the fact that it "died" and there is no time it can not be said that it did not exist?

is pure nonsense because there would be no "we", and so nothing that "we know", — Metaphysician Undercover

I rather thought "we" were "timeless observers".
I meant something like a line. At the end of this line ends the Universe. But this line "existed". In any space and in any time. So "we" as a timeless observer we can say that Universe "existed", when there is no time?