Jack, I just checked the testimonies. Both Jarman and Norman recall Brennan when they went outside. I found this from Williams...
Mr. BALL. When you got to the first floor, what did you see?
Mr. WILLIAMS. When we arrived to the first floor, the first thing I noticed was that the policemen had rushed in. I think some firemen came in with a water hose. And then the next thing that happened, these detectives, or maybe FBI--anyway, they stopped us all and they said, "Do you work here?" And we told them yes. And they took our name, address, and they searched everybody. And then the other fellow--I think one fellow asked whether we had been working upstairs. I think we told him yes. They got out all the fellows I think that was working on the sixth floor at the time, and they took us all down to the courthouse, I think, and we had to fill out some affidavits and things.
Mr. BALL. You made out an affidavit there?
Mr. WILLIAMS. Yes, sir.
Mr. BALL. Did you go out of the building shortly after you came downstairs?
Mr. WILLIAMS. They wouldn't let anybody out of the building.
Two points, firstly Williams recollection of Senkel asking for all those who had been on the 6th floor that morning. Recall that both Norman and Frazier fell into that category but somehow avoided going to City Hall.
Secondly Williams claiming they weren’t allowed out but he was filmed on the steps and did make it outside. I believe it was this statement that led me to believe only two went outside, it appears I was mistaken.