Oswald gave the time?
No note-takers said Oswald used the word "alone".

"said he ate lunch with some of the colored boys who worked with him.
One of them was called ‘Junior’ and the other one was a little short
man whose name he did not know."

— Fritz
Oswald gave the time?
"recalled possibly two Negro employees walking through the room
during this period."

— Bookhout
"said he ate his lunch with the colored boys who worked with him.
He described one of them as ‘Junior,’ a colored boy, and the other
was little short negro boy."

— Kelley
Yes, for some reason, I thought they took the back stairs. But the route they took would need the domino room door open and Oswald in a very tight area inside the domino room, in order for him to have seen them. And that doesn't relate to Oswald having the three in the same room eating their lunch together.
But then Oswald speaks of the two men being in the domino room having lunch with him. This is without mentioning that there is no evidence that Oswald took a lunch to work or bought lunch.
Oswald gave the time?
Duh!..... No, Lee did NOT give the time when he saw Jarman and Norman walk by....Jarman said that they left the front of the TSBD to go to the fifth floor at 12:25 and they arrived on the fifth floor at 12:28.... That would place them near the Domino room at about 12:26.....And Lee Oswald saw them.....
Oswald speaks of the two men being in the domino room having lunch with him. No,... Lee DID NOT speak of Jarman and Norman or anybody else having lunch with him....He said he ate lunch ALONE in that 1st floor lunchroom. Lee would have known better than to claim something that could easily be shown to be a lie....And if he had said he ate lunch with whoever, the cops could easily have asked the party if they had eaten lunch with Lee Oswald.....Nobody ever asked Jarman or Norman if they had eaten lunch with Lee....