If memory serves, 9.5 SP2 utilized the Windows 8.1 version of WinPE - which means you'd have to find a 32 bit Windows 8.1 driver for that device if you're hoping to boot it into WinPE for imaging. I looked here at Lenovo's Support Site for this box and it looks like they only offer Windows 10 drivers.
Intel, however, does appear to have some drivers available on their Support Site Here. You'll want to download the PROWin32.exe file for this job.
Once you have that file, you'll want to crack it open and look for the INF files present and test those on this Lenovo device while its in WinPE. See this document here on how to do this: How To Test Drivers Compatibility Within Winpe
Once/if you identify the INF file that gives you an IP Address, go ahead and inject that into the WinPE Image and redeploy PXE Reps. You should be good to go. If none of the INF files present give you an IP, we recommend you contact the vendor for more assistance .
Also, regarding your issue with booting the device in UEFI mode, UEFI doesn't come with a Network Boot Menu for PXE Booting. Our PXE Rep is expecting a menu response on Version 9.5 SP2, which UEFI doesn't provide. In order to PXE Boot UEFI in this version, you'll have to schedule a template to a bare metal/previous instance of this device in the console and then PXE Boot the device. It'll pick up the job and run with it. We added a feature to the console back in the 2016 version that'll handle this sort of thing:
Hope this helps. Good Luck!
Aaron