Video illustration
An illustration of the problem is at illustration_of_problem.webm
To view the video, you have to download it.
I also uploaded the video below. You can see the issue from the 1 minute mark onwards. I am sorry the video is pixelated. The video looks good locally but becomes pixelated when I upload it... The github repo contains a video file you can download and view with high quality.
Step to reproduce the problem with collision object and attached object passing through each other
roslaunch panda_moveit_config demo.launch
Add the motion planning plugin in Rviz and configure the plugin by changing the values of a few fields. This is described in step 1 of the quickstart in rviz tutorial http://docs.ros.org/melodic/api/moveit_tutorials/html/doc/quickstart_in_rviz/quickstart_in_rviz_tutorial.html
Run catkin_make in this directory
rosrun attach_obj_melodic planning_with_obstacle_movegroup_api_panda
Press Next in Rviz until both the torus and the cylinder is added to the world, with the torus being attached to the robot
If the torus does not become attached, manually attach it to the link 'panda_hand' by clicking on the checkbox correponding to the torus under the Scene Objects tab in Rviz
Perform planning using the GUI in Rviz