Oswald had to have stepped down a few steps to get his right forearm upraised w/bottle captured in Altgens 6 photo z255.
The act of taking a drink at this point suggests that Oswald was unaware a rifle shot had been fired at Z223 and that Oswald had no LOS to JFK . Otherwise, the effect of JFK slumping over coincident with a loud noise should have been sufficient to cause Oswald and others at the front steps to show some signs of reaction more pronounced than casual activity.
Instead, the TSBD front step crowd
seems to have been about as unaware as dodo birds to the fact shots were fired and the POTUS was hit, until Gloria Cavalry informed them.
This may explain the absence of any comments by Oswald during his interrogations of hearing/seeing shots fired, or seeing JFK hit,
Or it could be such comments were left out of the Fritz record (similar to Hosty) since description of such event might further substantiate Oswald’s presence on the front steps at the time of the shooting.