The reason for the time discrepancy, in my opinion, is that Kim left the argument with the players about money out of her statement.
Frankly, I think Kim and Precious were locked in the bathroom for some time. Kim makes reference to this in her statement when she says she "finally" came out of the bathroom. She also says Precious was going nuts when the guys were repeatedly knocking on the door. The players also say they had trouble getting the strippers out of there. I think then, when it became clear that the show was over and Kim was leaving, the players demanded a refund. Kim refused and an argument started in the house and eventually spilled out into the alley and was heard by Bissey.
Where was Precious? Probably stumbling her way out of the house and thinking about how she was going to get home. Her driver wasn't due for some time so she tried to get through to her escort service at 12:26 and probably staggered out of the house around that time. She fell down the back stairs and was on the ground for a few minutes before the guys managed to get Kim to get her out of there.
There is no time discrepancy. Careful reading of Kim's statement indicates that Kim left the bathroom, Precious followed her to the car, then left to "make more money," according to Kim.
Here is the part in the end
"forgot to mention that the first time Precious came to the car she left because she felt there was more money to be made. It was after then, that the boys helped her to the car. They carried her by throwing her arms over their shoulders and assisting her walking to the car - I can't remember if only one boy helped or 2."
So, clearly, Precious came to the car and then left.That must have been around 12:20, when she came to the car, and around 12:30, when she tried to go back. Then, she either fell or passed out on the stairs.
After that, boys helped her to the car.
This is the part that Kim says was less than 5 minutes - when she "finally" left the bathroom with Mangum still in there. If this ever gets to trial, this will become absolutely crucial testimony.
Mangum made a call at 12:26 and was out on the steps about 4 minutes later, so presumably Kim left before Mangum made the call, probably by a minute, which makes sense - Kim leaves the bathroom, Mangum doesn't know what to do and can't make decisions for herself because she's so out of it, so she calls someone almost immediately for a ride or what to do now - something like that. So, it's reasonable to assume that Kim left the bathroom at 12:25. Even if it was a few more than five minutes that Mangum was out of Kim's sight - put it at eight or nine minutes with Kim leaving the bathroom at 12:20 - Reade was long gone. Since Mangum identified all three boys as being together in the bathroom gang-raping her at the same time, yet Reade could not have been there as we already know, then neither could the other two have been there.