The way Wambui ran in Huelva leads me to believe she too has at least 2-3 seconds in the tank. Remember she is the youngest of them all by far, so she has a lot more potential to grow and get faster. Same thing for Niyonsaba, which we saw today: even without Semenya's "help" she pulled off a huge 1:56 today..
Semenya has had two 1:56-half races this year and she hasn't even been trying. She has not ran a single 800m at 100% and is already easily running under 1:57...if these hormone rules aren't normalized Kratochvilova's doping WR will be absolutely shattered very soon, possible even in Rio already.
1. Semenya will win that fight if these ridiculous hormone rules don't change, the only question is when.
2. Hard to tell, but I think both can definitely go under 1:56 or even faster.
3. That's the only real hard thing to tell...the likes of Sum, Arzamasova of course all have a medal chance, but they need their best day ever and a bad day for Semenya/Niyonsaba/Wambui. Which is of course always possible, like said before, nothing is sure and there are always favourites who fail.