So the other day I was dealing with a Surface Laptop device, brand new out of the box. Once booted up into WinPE, the integrated keyboard on the Surface Laptop did not work.
To fix this you need to load the following .INF’s from the MSI driver pack from Microsoft to the boot image. Can be downloaded from here.
As I have only tested with one model/ version of this laptop, it might be wise to “DRVLOAD” each on of these INF’s first before adding it to the boot image to verify that it is working on your model as well.