I'm not sure that this is correct, but:
There are 16 cards, 4 aces and 12 non-aces.
The first player must get 1 ace out of 4 and 3 non-aces out of 12: 4C1 · 12C3 = 880.
This is out of a total of choosing 4 cards out of 16 cards: 16C4 = 1820.
The probability that this occurs is: 880/1620.
There are now 12 cards, 3 aces and 9 non-aces.
The second player must get 1 ace out of 3 and 3 non-aces out of 9: 3C1 · 9C3 = 252
This is out of a total of choosing 4 cards out of 12 cards: 9C4 = .495
The probability that this occurs is: 252/495.
There are now 8 cards, 2 aces and 6 non-aces.
The second player must get 1 ace out of 2 and 3 non-aces out of 6: 2C1 · 6C3 = 40
This is out of a total of choosing 4 cards out of 8 cards: 8C4 = .70
The probability that this occurs is: 40/70.
There are now 4 cards, 1 ace and 3 non-aces.
The second player must get 1 ace out of 1 and 3 non-aces out of 3: 1C1 · 3C3 = 1
This is out of a total of choosing 4 cards out of 4 cards: 4C4 = .1
The probability that this occurs is: 1/1
Now, we need to multiply these together: (880/1620) x (252/495) x (40/70) x (1/1) = 8 870 400 / 56 133 000.