[Dynasty]

In step two, you are counting flops that contain two or more A's or K's multiple times.

I don't think so.

My calculation was: Step 2: The number of A,x,y or K,x,y flops are 4 (number of Aces and Kings left in the deck)*28*27/2 = 1,512

I'm not even counting the flops which contain two or more A's or King's- not even once. I'm only caculating the probabilty of floping a pair of Aces or a pair of Kings. x and y cannot be either an Ace or King. The 28 (and 27) used in the calculation is 52 -4 Aces -4 Kings -16 non Ace/King cards in other players' hands. 52-4-4-16 = 28.