
Essen
Well this is unfortunate ...
oh I made like triple sure about upside/backside and each line between the manufacturer datasheet and the board footprint with the net labels attached, on the adapter board between "RJ45" and shrouded 0.1" pitch header and shrouded 0.05" pitch header I did to use the RJ45-tailed version of the Tag-Connect 6-pad noclip cable with a black magic debug probe (and also offer ragular 0.1" pitch header pinout in case of use with something like JLink or such).
Those connectors are unusually evil in terms of footprint ambiguity.