Well, you led me in the right direction. All the ID's were properly activated. What happened is the first thing I did was create a new Sheet Index so I wouldn't screw up the default one. When I did that an Add Project Index window pops up. At the top is a Use With line that selects View, Layout, Drawing lists. Assuming it defaulted correctly I didn't touch it. However, it just defaults to View. At that point I was stuck. It didn't even occur to me to check the default index, but it worked fine. This time I created a new Layout list and it works fine.
Mac OS12.6 AC26 USA Silicon
M1 Macbook Pro