Are you sure about that ?

That implies SiLabs are making a twisted-lead cable, which makes little sense in production. Too Labour intensive.
Most suppliers would do that shuffle on the PCB.

That means the Debug units would not be identical, but can be 'crossed over', with special crossed cables / headers.

This needs a reply from someone who has _actually_ connected an older SiLabs Debug dongle, to a M3, and vice versa.
Seems Silabs are confused here too..

Given the PITA of making crossed cables, this is probably easiest solved with a tiny paddle board, IDC-in to Female-out, that shuffles as needed.

It also is more obvious than a crossed cable.