public core data not syncing with cloud kit

Since "The "out-of-the-box" implementation of CoreData / CloudKit sync does not, and will not, store any records in the Public database" how does one go about storing records in the public database (when I look using the CloudKit dashboard, there are only private records, nothing in public)?

I know about setting databaseScope = .public in NSPersistentCloudKitContainerOptions, and about assigning freshly created managed objects to the appropriate scope (needed because my app has more than one). What else do I need to do to get syncing to work?

i also notice that canModifyManagedObjectsInStore returns NO for the public store, which apparently means that my public core data is not backed by CloudKit (how do i fix that?) or some other issue (can anyone suggest why that might be?). maybe this gets me closer, but it just changes the questions into different ones for which I still can't find an answer.

and yes, i do know that i have to add two new [QUERYABLE] indexes (for recordName and modifiedTimestamp) to each of my record types. this did not get my public data into CloudKit

I have a similar that I can't sync Core Data record to public database in the last few days. The CloudKit backed private database is working fine.

public core data not syncing with cloud kit
 
 
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