trouble with animating FK\IK switch

I’m trying to do an animation with FK/IK switching in the middle. it worked find until I did some retiming and for some reason the keyframe of the costume property didn’t move. I checked and it wasn’t in the list of the dope sheet. so I couldn’t move them. but they were still exist. Can someone solve this mysterious for me?
(my english is not the best but I hope you understand)

I understood it’s a problem with the rig? I didn’t make the rig I’m using.

I found them in the list if I reveal the ik layer. is it an expected behavior? I don’t think so. I should see every thing that is animated in the dope sheet, souldn’t I?

Two bones on different bone layers will only show up together in the dope sheet if both those bone layers are visible. To see all bones (and all other animated invisible objects in the scene), toggle the ghost icon in the Dopesheet window.

If it is a custom property keyframe, perhaps it is hidden somewhere in the folds of the dopesheet. Depending on what datablock that custom property is attached to, you might not see it under the same list as the bone keyframes.

I made custom properties for the armature object, the armature, and a bone. Here’s a screenshot of where they show up in the dopesheet.

Thanks! help me. I will remember to enable ghost the next time.