Answer remains the same
As far as legal, moral, and ethical justification goes, if somebody wants to use a weapon to rob or coerce me, they are fair game until they cease in such attempts. I am not going to attempt to read their minds to determine if they really want to do me any harm.
So, would I feel justified in use of lethal force? Yes.
Would I use lethal force? Maybe.
The answer to that question would depend on if I felt I could get clear sightlines, avoid endangering other victims, etc.
But no way on earth am I being herded into a room. If they try that, there will be a fight.