Different device issue, but we found for one laptop that all drivers that should have worked for the device failed for varying reasons. It wasn't until we found their 'Windows Blue' drivers that we found ones that worked. It may be worth keeping an eye out for something like that in case it's a similar issue.
Try this; in the BIOS change the SATA section (sorry, I had Lenovo's before and don't have one now so can give you exact wording of the BIOS menu) look for AHCI and Compatible. Choose compatible.
If that works, best bet is to switch back to AHCI prior to first boot of Windows so it can see the SATA is capable of AHCI or else you will have to add the "multi-proc" driver later on in Windows (not a big deal but just should be done). In fact now I remember you may have to leave the setting as compatible until after first boot because Windows may BSOD on first boot. Experiment, then comment back on this thread.
Thanks for the reply guys. Ironman, I have used that fix in previous years, but unfortunately does not help in this case. We have upgraded to 9.6 SP2 and out of the box WinPE works with these devices, although i am not sure why since 9.5SP3 uses the same version of WinPE and both require Win8.1 x86 drivers. So I guess I will now close this.