Looks like we can't reproduce the issue or there's a problem in the test case provided.
selectionchange does not fire on NestedList
The docs mention "selectionchange" event to be available on NestedList. But it does not fire when selected item(s) change in the currently active view.
NestedList code also does not contain anything that fires this event.
My current work-around is to add a selectionchange listener to each card list using the defaults option on NestedList.
This has already been fixed for the next release.