Collusion?

What do you think.. SB left after this hand, c/o left a couple of hands later, both were fish. Guy who "won" the hand spun up his $1500 to $6k, the other did $1500 twice in quick fashion. The one with $6k was there a little while before the other.

Game #3765388293: Hold'em NL ($25/$50) - 2007/04/09 - 16:23:28 (EST)
Table "Abramov" Seat 5 is the button.
Seat 1: lundgren1 ($5694 in chips)
Seat 2: dankiiii ($6749.14 in chips)
Seat 3: AceHole ($5948 in chips)
Seat 4: Pau080570 ($3524.57 in chips)
Seat 5: JPK69 ($4800 in chips)
Seat 6: Sim100517 ($1870.60 in chips)
Sim100517: posts small blind $25
lundgren1: posts big blind $50
----- HOLE CARDS -----
dealt to JPK69 [Qh Jh]
dankiiii: folds
AceHole: folds
Pau080570: calls $50
JPK69: raises to $200
Sim100517: calls $175
lundgren1: folds
Pau080570: raises to $350
JPK69: calls $150
Sim100517: raises to $500
Pau080570: calls $150
JPK69: calls $150
----- FLOP ----- [Jd Ks 9s]
Sim100517: bets $1370.60 and is all-in
Pau080570: calls $1370.60
JPK69: folds
----- TURN ----- [Jd Ks 9s][Kh]
----- RIVER ----- [Jd Ks 9s Kh][6h]
----- SHOW DOWN -----
Sim100517: shows [Td Ad] (A Pair of Kings, Ace high)
Pau080570: shows [Jc As] (Two Pairs, Kings and Jacks, Ace high)
Pau080570 collected $4288.20 from Main pot
----- SUMMARY -----
Total pot $4291.20 Main pot $4288.20 Rake $3
Board [Jd Ks 9s Kh 6h]
Seat 1: lundgren1 (big blind) folded before Flop (didn't bet)
Seat 2: dankiiii folded before Flop (didn't bet)
Seat 3: AceHole folded before Flop (didn't bet)
Seat 4: Pau080570 showed [Jc As] and won ($4288.20) with Two Pairs, Kings and Jacks, Ace high
Seat 5: JPK69 (button) folded on the Flop
Seat 6: Sim100517 (small blind) showed [Td Ad] and lost with A Pair of Kings, Ace high