P(4 wins) = P(4 beats 1) P(4 beats the winner of the other bracket)

P(4 wins) = (1/5) * [ P(4 beats 2 | 2 beats 3) + P(4 beats 3 | 3 beats 2) ]

P(4 wins) = 1/5 * [ (3/5)(2/6) + (2/5)(3/7) ] = 78/1050 = 0.0742

For the other teams:

P(1 wins) = 4/5 [(3/5)(2/3) + (2/5)(3/4) ] = 0.56

P(2 wins) = 3/5 [(4/5)(1/3) + (1/5)(4/6) ] = 0.24

P(3 wins) = 2/5 [(4/5)(1/4) + (1/5)(4/7) ] = 0.1257