What would a power management tab do if the notebook is powered off? There are normally 2 settings: Allow to wake up the PC and Allow to power off the hub to save power. Both aren't relevant in your case.

Some bios allow for charging on certain USB ports- checked that?

Since the docking station has its own power supply- how should it know what to do with the disks when the USB host is powered off? You might as well simply switch it off by hand? And it might be the firmware of the docking station. There isn't even mentioned what kind of USB-SATA bridge they're using, if you'd know that you could search for another device that has a better firmware. If I remember right, when I searched for my device there were several firmwares out which also were different in suspend behaviour.

So this seems not at all to be related to the Renesas driver- use the latest linked here.