This is what the SECOND FBI interrogation report has to say:
OSWALD stated that on November 22, 1963, at the time of the search of the Texas School Book Depository building by Dallas police officers, he was on the second floor of said building, having just purchased a Coca?cola from the soft-drink machine, at which time a police officer came into the room with pistol drawn and asked him if he worked there. MR. TRULY was present and verified that he was an employee and the police officer thereafter left the room and continued through the building. OSWALD stated that he took this Coke down to the first floor and stood around and had lunch in the employees? lunch room.Sarah Stanton's encounter with LHO-with-a-coke BEFORE the assassination, BEFORE the search of the Depository building, tells us that the above chain of events is a
LIE.
But whose lie is it?

Well, seems to me
-------------->LHO (guilty or innocent) would have had
no reason to hide his pre-shooting visit to the coke machine.
-------------->the investigators would have had
every reason to do so!