OK, fine, but doesn't that leave the same issue as to why Oswald thinks he's been framed? Say the rifle was removed from the garage two weeks previously, or a month, or whatever. Or it never was in the garage. I don't see any way that Oswald realizes he's been framed within minutes of the assassination unless the M-C actually was his rifle and he knew it was in the building. What other scenario is there where he realizes "I've been framed for the assassination of JFK and I need to hightail it out of here and get my revolver." Even if he'd been a knowing cog in some event he didn't think was an assassination (perhaps a protest of some sort), and then realized it was an assassination, it's hard for me to make sense of his subsequent actions on that basis - unless he knew his rifle was in the building.
It's 2-3? minutes after the "event" that took place outside the building where he works. He's having lunch, hears this commotion outside, a police officer confronts him and lets him go, someone says the President was shot or maybe not. This is all he knows.
So he goes outside, sees this absolute chaos taking place, police running around with guns drawn, people yelling and screaming. Many people are going to the grassy knoll, the fence, the overpass. Some say the President was shot. Others say otherwise. It's all confusion.
From this limited information the innocent Oswald determines he's being framed? For what exactly? How can he be framed? He's having lunch. He doesn't know where the shots came from.
Moreover, during his journey from work to the rooming house he never inquires about what happened. He doesn't talk to any co-workers, he shows no interest in learning about what happened, he ignores the TV that is on as he goes to his room, he doesn't ask Roberts about any news. For a guy thinking he's being framed he sure doesn't want to find out anything that might help exonerate him. Not exactly Richard Kimble looking for a one armed man.
The very political Oswald shows
no interest at all in what happened. In this world, none of this makes sense. In Oswald defender world it's all assumptions and suppositions.