Hi,
I deslodered, flashed, soldered back the eeprom on SATA Sil with pointed firmware. Mac OS X boots normaly from Sata SSD, MorphOS same state ... no storage...
Class : Unknown SubClass : Device Does Not Fit ... in PCI boot.
It is strange because you reported that FW works.
I changed disk from SSD Adata SU650 to some small rotation disk from NTB, what I have and it is visible in MorphOS, then PCI information about Class and Subclass seems to be irrelevant for reading disk in MorphOS. If disk is not recognized in MorphOS, then sata bus card is not displayed ...

Ok, then this is now about looking for SSD disk which is visible in both OS, Mac + MorphOS.
Thank you
f.