tree diagram uses the persons data and data could consist of personality, ability and preference or even their characteristics. Accelerator's data had been used in tons of other projects of academy city so it's only natural that they know his behavior. And besides the psycho scientist that takes care of accelerator is doing the work. Do you think that psycho wouldn't take that into account in the battle simulation? plus the whole number thing is a farce anyway and I wouldn't believe it.
Because if you see in the battle with an angered mikoto vs accelerator who's paying around. That's a complete one sided and the moment accelerator get nears on mikoto that should had been game over but his not doing it. Instead he just toys with his prey.
And come one let's discuss on what would mikoto do next on now that she knows tree diagram is destroyed. I always tries to shift the discussion on the current manga that's been scanned or release but it always ended up if mikoto could take on the upper ranking or lower ranking. It's turning into a battle or power level discussion instead of the manga discussion.
I wonder if we will get to see uiharu and saten on the next chapter. And what would kuroko do. We know that she would help touma a bit with information but what would be her reaction when she saw her onee-sama devastated form.