NSMetadataQuery not searching subdirectories in external ubiquity container

Testing Environment: iOS 18.4.1 / macOS 15.4.1

I am working on an iOS project that aims to utilize the user's iCloud Drive documents directory to save a specific directory-based file structure. Essentially, the app would create a root directory where the user chooses in iCloud Drive, then it would populate user generated files in various levels of nested directories.

I have been attempting to use NSMetadataQuery with various predicates and search scopes but haven't been able to get it to directly monitor changes to files or directories that are not in the root directory.

Instead, it only monitors files or directories in the root directory, and any changes in a subdirectory are considered an update to the direct children of the root directory.

Example

• iCloud Drive Documents (Not app's ubiquity container)
  • User Created Root Directory (Being monitored)
    • File A
    • Directory A
      • File B

An insertion or deletion within Directory A would only return a notification with userInfo containing data for NSMetadataQueryUpdateChangedItemsKey relating to Directory A, and not the file or directory itself that was inserted or deleted. (Query results array also only contain the direct children.)

I have tried all combinations of these search scopes and predicates with no luck:

query.searchScopes = [
  rootDirectoryURL,
  NSMetadataQueryUbiquitousDocumentsScope,
  NSMetadataQueryAccessibleUbiquitousExternalDocumentsScope,
]

NSPredicate(value: true)

NSPredicate(format: "%K LIKE '*.md'", NSMetadataItemFSNameKey)

NSPredicate(format: "%K BEGINSWITH %@", NSMetadataItemPathKey, url.path(percentEncoded: false))

I do see these warnings in the console upon starting my query:

[CRIT] UNREACHABLE: failed to get container URL for com.apple.CloudDocs
[ERROR] couldn't fetch remote operation IDs: NSError: Cocoa 257 "The file couldn’t be opened because you don’t have permission to view it."
"Error returned from daemon: Error Domain=com.apple.accounts Code=7 "(null)""

But I am not sure what to make of that, since it does act normally for finding updates in the root directory.

Hopefully this isn't a limitation of the API, as the only alternative I could think of would be to have multiple queries running for each nested directory that I needed updates for.