My experience of two apparently identical Lenovo machines is that there can be significant differences. When I was creating images for a large library of Lenovo desktop and laptop machines a couple of years ago, I wrote the utility described here: https://www-secure.symantec.com/connect/articles/readyutility-assist-identifying-plug-and-play-drivers
This gave me a heads up on exactly what devices were present in each machine I worked on. As you may see from the Lenovo driver downloads offered for a specific model, it is not uncommon for network drivers to include Intel and Broadcom, and the video drivers to include AMD and NVidia, so clearly different chipsets are being used in what purports to be the same model.
Another issue I encountered were differing BIOS releases and more importantly different BIOS settings.
For example, if you create a build on a Lenovo machine where the bios hard disk settings are in "compatibility mode", and then deploy it to a machine where the bios settings are in "AHCI" mode, the image is unlikely to deploy as the hardware will be expecting SATA drivers to be loaded to provide access to the hard disk where previously the "Compatibility mode" would have forced emulation of the original PATA standard which ALL windows operating systems still support natively.
The fact that you are using WinPE with default drivers is ringing alarm bells in my head, as the version of WinPE supplied with ghost only supported some of the first generation of SATA chipsets and I had to load additional drivers for what were modern machines three years ago.
In summary, for two machines to be identical, they have to have the same revision of motherboard, the same bios version, the same bios settings, the same model and revision of hard disk, the same model and revision of optical drive, the same model and revision of video card, The same model and revision of NIC chipset, the same model and revision of USB chipset, etc. Just because they have the same model number does not guarantee ANY of these being the same, as the specifications of a model are based on high level parameters such as processor speed and disk capacity and not on chipset versions.
Remember also that the machine vendors buy in parts, and these parts will come in at different revisions as the part manufacturers fix bugs and update their hardware, but as long as the new parts do not materially change the model specification, the vendors are just going to ship the new parts and let you sort out any consequences.
In summary therefore, if a process works on one of two "identical" models but not another, my attention would focus very closely on what is different between these two "identical" models, and I would not exclude the possibility of hardware failure such as a RAM fault either. A lot of time has been wasted by techs over the years where the issue proves to be a dodgy bit of memory.