Install Windows 10 32 bit on M.2 drive

I have an M.2 drive that I'm currently trying to install Windows 10 x32 on (we need the 32 bit version for work apps). Installing Windows 10 x64 works just fine, but trying to install the 32 bit version from the same Microsoft-provided USB install stick doesn't work.

Facts:

• In UEFI boot mode, the install works for x64, but doesn't even get to the Start Install page for x32:

• In Legacy mode, I get the Start Install page, but when I get to the Select Partition page, Windows won't let me install onto my M.2 drive. I don't have this problem for x64.
  The popup is what you get when you click the Windows can't be installed on this drive link on the bottom. If you ignore that and click next, it will give you the following screen.
  

• This is different than the GPT/MBR error. I've also tried formatting the disk, and converting it between GPT and MBR. No dice.

• I get the same message whether run the installer on my laptop (Lenovo T470p -- where the drive will eventually be going), or desktop (Dell OptiPlex 3040, through a PCIe adapter).

• I've installed and booted Win10x32 installations on the desktop before, so I'm doubtful it's a hardware problem on that side.

Note that the M.2 drive came with the laptop, and the specs say it should be compatible with Windows 10 x32. We've spoken with tech support (shutter), and they've confirmed this as well, but they weren't able to tell us how (at least not at the level we got to).

Research:

According to this dell support page,

Supported BIOS Types

• The UEFI BIOS is currently the only one which supports these devices.
• Always make sure you have the latest revision of your BIOS installed.
• Make sure that your BIOS is configured to use the EFI boot loader.

This may or may not be applicable to Lenovo systems as well.

I've seen a bunch of questions on the internet (and SU) on how to install Win10x64 if that's not working, but my question is specifically about the 32 bit version, since the 64 bit version works.

Is there anything I've missed? I'd be more than willing to try out a list of configurations if you need more info; I've pretty much hit a brick wall. We ordered another M.2 drive that should get here today as well. I'll update with how that one goes.

Edit: Different than this question. That question is for 64 bit installs, and I've tried the suggested answer there (removing all other drives), to no avail.