Hi.I found a bug probably
The Root bone is selected, key frame does not show all the DopeSheet
It was a project where there are skeletons of three hierarchy.
The skeleton of one, if not to the Hidden Root bone, Animation key frames of all the children did not appear on the Dopesheet them.
I think you have to do is choose the Root bone that is displayed normally, key frame of the child is to be displayed in all Dopesheet.
the selected Root bone of the skeleton of other key frame related was displayed in all DopeSheet.
Thank you.