Basemap Gallery Widget - Missing Basemaps under Configure Custom

[RiverCOG]

Using the Web App Builder I would like to be able to specify a subset of basemaps that the user can switch to. However when I select the "Configure custom basemaps" radio several of the basemaps become unavailable that use the basemaps.arcgis.com rest. (See attached images)

Only 12 out of the 28 ESRI Default basemaps can be selected for a custom view. 

When trying to add any basemap that uses the https://basemaps.arcgis.com/arcgis/rest/services/World_Basemap_v2/VectorTileServer it states "This type of layer cannot be used as a basemap" but it clearly can be used as a basemap when the full ESRI Default is selected. Where do I find the appropriate URL for the basemaps in the World Basemap v2 Layer?

Thank You.