Oswald was out front of TSBD on the entrance landing in the west corner.
He’s the Prayerman drinking the white label Dr.Pepper which was left at the lower step he was standing on thus making his 5’9” height appear only 5’2” relative to the 6’1” Buell W. Frazier.
The timeline starts from the 12:25 location of Oswald in the Domino room and because of FBI Hosty and Caroline Arnold, the late 12:29 arrival is Oswald to the outside landing and in position of PM, unnoticed , is entirely possible.
PM is NOT 300lb 5’5 “ Sarah Stanton
PM is NOT Pauline Sanders because she was over at the EAST side of the landing and right in the path of Baker running up the EAST side of the steps , which the primary reason Pauline Sanders saw Baker while seems to have missed seeing him.
No other person has come forward to positively ID themselves or a relative or friend they knew, as being PM.
The reason Oswald did not shout out nor some to wife, mother or brother , that he was on the steps at time of shooting , could plausibly be that Oswald thought he needed a reliable attorney before he divulged such info, lest the authority’s might destroy photo /film or alter photo or film.