Ask and ye shall receive (sometimes...but this is one of those times!)
The math on this is actually pretty hairy, so I ran a simulation instead, 100,000 repetitions. It's not perfect, but the numbers will at least be close. (All of the simulations also simulate the coin flip for positioning.)
Obviously, if both WAS and GSW win tomorrow, we're all alone in 3rd, and the values found on the Wiki page are accurate (though ties below us might make a wee tiny difference in the overall numbers):
#1: 15.6%
#2: 15.7%
#3: 15.6%
#4: 22.6%
#5: 26.5%
#6: 4.0%
If we are in a tie for 3rd-4th, the probabilities (via simulation) are:
#1: 13.6%
#2: 14.3%
#3: 14.3%
#4: 16.3%
#5: 30.9%
#6: 10.0%
#7: 0.6%
If we are in a tie for 3rd-4th-5th, the probabilities (via simulation) are:
#1: 12.1%
#2: 12.7%
#3: 13.5%
#4: 10.6%
#5: 29.1%
#6: 18.6%
#7: 3.2%
#8: 0.1%
Edit: And in the time it took me to write the simulation, Hammystyle just averaged the numbers and got substantially the same result. And here I thought that averaging was going to get it wrong. Heh.