Yes, I thought about the bathroom too and how she would have almost certainly noticed someone was in there when she first walked into the house. The light would have been on, since it was night. Also, Rudy would have turned on other lights as he was making himself at home in the house.
But the lights, Meredith could have thought it was Amanda at home.
So....if Rudy was in the bathroom, she would walked in on him as he was sitting on the toilet. So the initial struggle would have to have made with his pants down. Unless she for some reason just started talking to him, and then he suddenly decided to jump on her and murder her, I don't see this as a possibility.
Wouldn't there have been signs of a struggle then, beginning from the large bathroom? Furthermore, I don't know when he would have had time to pull his pants back up until after the murder, as doing that would have temporarily let Meredith go free.
If he was in one of the bedrooms, she would have walked past the broken window, the draft of cold air, etc.. The light could have been on or off in that room. If the light wasn't on in the living room, she would have probably turned it on, and turned a light on to go down the hallway, so the light would have shone in Filomena's room. And feeling the cold draft, she would have looked into the room, IMO. Seen a broken window. At that point, she wouldn't have proceeded any further, I am absolutely sure of that. No girl in their right mind would continue on in a house at night when they know someone's broken in. So she stopped, immediately started go back out the door, Rudy would have come then and grabbed her, the struggle would have started in the living room.
If he was in Filomena's room, the struggle would have started there and Meredith walked up on him in that room (due to light being on and her walking past the room, also cold draft).
So.....that leaves the question.....
How does one get to her sitting on the bed taking her shoes off with her back towards the door, with Rudy in the house?
OR.......
Rudy enters the house through the broken window after she's already in the house. How does one get to her sitting on the bed taking her shoes off with her back towards the door, after hearing window break?