Correct. My 750w G2 are setup similar to your PSU2 above, CPU to 2x 6pin splitter and using 1 molex string per riser.
(I had spare EVGA G2 molex cables, and on the PSU side PERIF/SATA sockets are wired the same)
So I can use the Perif - Molex cable in the SATA plugs on the PSU as well?
EVGA G2? Yep, the sockets are the same other than labels.
Seems to be common for EVGA PSUs, I've noticed it with G1, G2, GS and PS series. (all of which conveniently use the same modular molex cable pinout)