You're right, I didn't see that it's not labeled IC602. However, I'm not totally sure it's the IC6 either. While that looks like the right type of chip, the position on the PCB seems wrong. Usually, the IC602 is located closer to the main IC. I'm thinking that IC2 is actually the one to transfer to the position of the IC602 on the SATA board.
I don't have one of these PCBs here to really take a close look and see for sure. However, my assumption of their labeling scheme is that:
IC602 was abbreviated down to IC2
IC606 was abbreviated down to IC6
they just omitted the "60" inside the labeling.