Not having the winning hands memorized, I googled winning poker hands and came up with this answer:
http://govegas.about.com/cs/gambling...kerhandstp.htm
If another 4 was drawn, then player 2 wins. Three of a kind does not beat a straight. Therefore, since both players would have a straight, the high card holder would win. In this case, King high would win.
The 2% issue is a little more difficult. Since there are at least two 4's already out, the chance of pulling another 4 would probably be around 2 in 32 (assuming 6 players at the start - 12 dealt to players, four shown, four wasted). This would give about 6% chance to draw a four. From the 2% figure, I am going to assume they "knew" another four had already been wasted and then also rounded down. I am not 100% on this theory though.