The definition of the term self check in the glossary should be changed. It says:
Action of the thrower touching the disc to the ground to restart play, taken when no defensive player is within reach of the thrower.
This definition does not include case 10.5.3:
10.5.3. if the disc is not within reach of a defender and there is no thrower, the defender nearest to the disc must call “Disc In”.
When exactly is the moment when the disc is in after a check/self check?
The glossary says it is the moment the disc is touched. The rule says the disc has to be touched and the words "Disc In" have to be uttered.