Windows command interop in WSL does not work, reports not found for all commands

Environment

Windows build number: Microsoft Windows [Version 10.0.18363.1198]
Your Distribution version: [On Debian or Ubuntu run `lsb_release -r` in WSL]
Whether the issue is on WSL 2 and/or WSL 1: Linux version 4.19.128-microsoft-standard (oe-user@oe-host) (gcc version 8.2.0 (GCC)) #1 SMP Tue Jun 23 12:58:10 UTC 2020

Steps to reproduce

Installed Docker Desktop and the patch to update WSL to 2 by following these instructions WSL Install Instructions but then installing Docker Desktop instead of a standalone distro.

Then:

    C:\Users\User>wsl -l -v
      NAME                   STATE           VERSION
    * docker-desktop         Running         2
      docker-desktop-data    Running         2

Note I have no additional distribs installed other than what Docker installs itself.

Run wsl to start the default distrib which wsl -l -v indicated was docker-desktop. Then from inside that distrib execute a simple Windows command using interop as described in the documentation Run Windows Tools From Linux

C:\Users\User>wsl
DESKTOP-SDE0C3N:/tmp/docker-desktop-root/mnt/host/c/Users/Martin# cmd.exe /C dir
-sh: cmd.exe: not found

<--
Collect WSL logs by following these instructions: https://github.com/Microsoft/WSL/blob/master/CONTRIBUTING.md#8-detailed-logs
-->
That's a 15 minute process! Don't you have a half reasonable method of getting some logs?

Expected behavior

I'm expecting cmd.exe to run.

Actual behavior

It fails with Not Found.

Reproduce the failure in the Docker Desktop docker-desktop WSL 2 distribution using cmd.exe /C dir, then review the linked Run Windows Tools From Linux documentation and CONTRIBUTING.md section 8 for logging. Done means Windows command interop works from the distribution and the failure is covered by an identified fix or documented cause.