Oswald told police and FBI interrogators that he was "out with Bill Shelley in front" during the shooting.
He must have meant during the shooting because Shelley did not remain out there after the shooting. Shelley left immediately, with Lovelady, for the railroad tracks. They were part of that throng of people who swarmed into that area to look around. Afterwards, they returned to the Depository, re-entering through the back door. Then, they were inside for a long time, until it was time to go to City Hall. Neither of them ever returned to the front to mill around.
We even have a picture of Shelley and Lovelady strolling along to the railroad tracks, and it was taken much less than a minute after the shooting.
Notice that Lovelady is wearing a short-sleeved shirt, as he told the FBI. So, he could not possibly be the Doorway Man.
The statement Oswald made to the reporter was framed by the reporter. He didn't ask Oswald where he was. He asked him if he was inside the building at the time. Oswald didn't qualify it; he just said yes. But, if you've ever been to the doorway you know it's like a cave. Standing where he was, Oswald was surrounded by building on 5 sides: left, right, above, below, and behind. Only to the front was it open to the outside. But, if you were in a cave, even though it had an opening, would you not describe yourself as being inside?
So, Oswald didn't qualify it to the reporter. He didn't shout out that he was in the doorway. But then again, he didn't know that his image was captured there. He died not knowing. But, it's the picture that makes the doorway significant, not that it was a doorway. For instance, if he was a couple of feet back inside the door, he could have watched much the same. He would have been properly inside, but how much different would it have been?
Oswald's alibi, the one he gave to police, is that he was standing in the doorway when JFK got shot, and his supervisor Bill Shelley was there. He could not possibly know that unless Oswald was there himself.