Hmmmm, well maybe my process is a little different than yours. I publish tile layers by themselves, so there's an Item Details page for the tile layer.
If you click on the "Settings" tab, you can see the number of tiles that are built for each level.
When I add these layers to a web map, they show up as "Tile Layer", not "Group Layer" like you have in your screenshot, which is why I mentioned that our workflows seem to be different.
Are you not able to see the group layers as distinct items in your content in AGOL?
Best,
Katie
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