Using the spreadsheet view to fill the blanks, it seems there’s no way to apply a filter that would list empty cells for a given item type. You could argue that those should be easy to find by ordering the column, but columns for item type are not sortable on my end (see my other ticket here).
Also, using filters on a specific value still display the parent item even if it should be filtered out, which is a bit unexpected. I’ve attached an exemple where I’m filtering Chapter 5, but the parent item is from Chapter 2 and still displays.
I personally think parent items that do not match the filtering rule should be filtered out. But I also understand that the UI still needs to indicate somehow we’re looking at child items with its parent not displayed (or not editable at least and greyed out (?), if still displayed). I’ll leave to you to determine the best approach if you decide to take this feedback into consideration.