If you will note the constrictions of Jerusalem in A.D. 30, there is no location in the city for the 120 to assemble and spill out to speak to any MULTITUDE of many nations (as listed in Acts 2:5-11, for example, except they of the 120 be in the Temple Mount and immediately spill out to the Court of the Gentiles at the Temple so that tens of thousands can be immediately affected.. Jesus spoke at Solomon’s Portico and taught.
The real upper room is connected to that same Solomon’s portico, and it makes sense to return to a location next to and adjoined to where Jesus spent 4 of his last days teaching from. Any other location than that is intentional disinformation by an unbelieving and hostile to Christianity Conspiracy academia who can’t date the New Testament accurately to its real history date, let alone the Exodus, nor decipher the Calendar Josephus used and how it, Greek history, and early Christian writings all agree on a 1551 B.C. Exodus from Egypt. To ruin all that prior and CURRENT teaching materials with the true reality and show them up as fools or liars? Shame!