1) The conversation O.P and Reeva apparently had before he gets up seems odd "can't you sleep baba?", "no i can't", surely she would have asked why or what's the matter?, sound's a bit made up.
2) Doesn't notice or hear her pick up her phone and roll from one side of the bed to the other whilst he is in the same room
3) No reason for Reeva not to turn any light's on on her way to toilet
4) Why would Reeva bother opening a window in the bathroom at 3am?, doesn't make sense.
5) O.P Hears the alleged noise and doesn't do the thing that every one on the planet would do in the same situation, i.e say "what was that?" "did you hear that?".
6) Picks up his gun and says "Call the police and get down"?, and thinks nothing of it when he get's no reply, surely you would make sure your partner understood exactly what you were doing
7) Just as he enters the passage he says "I shouted for Reeva to get on the floor, I shouted for her to phone the police, I screamed at the people to get out".
So nice of him to let the potential intruder(s) know there's a defenceless woman laying on the floor of his bedroom.
8) Then bizarrely gets near the entrance of the bathroom and decides he better not shout in case he gives his position away, after already doing that seconds earlier.
9) Hears toilet door slam shut but quite amazingly doesn't hear the door lock.
10) He's in the bathroom, he's screaming again at Reeva to call the police, he then say's he stood there for "some time" Reeva according to him has her phone with her, but yet Reeva doesn't phone the police?.
11) it is totally ridiculous to think Reeva wouldn't respond at this stage, she must be able to hear he is right outside the door.
12) The speed at which it dawns on him it might be Reeva in the toilet, doesn't ring true, i mean not even checking the bedroom door, do me a favour.
13) The alleged screaming like a woman, while he suspects it might be reeva in the toilet, the only thing he would have been doing is screaming the name "reeva" over and over.
It's just occurred to me that before the shot's Oscar is claiming that in bathroom this happened
"At this point I started screaming again for Reeva to phone the police. I wasn't sure where to point the firearm, I had it pointed at the toilet but my eyes were going between the window and the toilet. I stood there for some time. Not sure how long. I wasn't sure if someone was going to come out of the toilet to attack me. I wasn't sure if someone was going to come up the ladder, and point a firearm in my house and start shooting. So I just stared and I kept on screaming.
Mrs Stipp was awake Before the first set of sounds which according to Oscar were the gunshot's, he say's he was doing a lot of screaming literally just before the first set of sound's, so why did Mrs Stipp not hear them?, the first thing she hear's are the first set of sound's then screaming.