Seven things Jesus Christ did NOT say., page-106

other perspectives would be appreciated.

In the case discussed it is the personal tribulation of each and every one that no one could count, from every nation, tribe, people and language, standing before the throne and before the Lamb.
It's not an event.

In a sense, because all will be restored, every person ever, will go through it.
That's not to say that it will be the case.