Before Kodi 17, there was one command and that was CodecInfo.
With Kodi 17 CodecInfo was retired and replaced by PlayerProcessInfo (CodecInfo still works but shows the same overlay as PlayerProcessInfo).
The new PlayerProcessInfo has way less information then the old CodecInfo (aq/vq, bitrates, framedrop/skip).
These numbers are now found in PlayerDebug.
The question remains, why i can’t map it…should be possible.
I edited the keymap.xml in macOS TextEDIT (plain text), saved as Unicode UTF-8 - maybe there are missing CR characters or something?