ULevelSequence::CreatePossessable() doesn't work in packaged build

I need to allow the player to edit a level sequence at runtime, i.e. add/remove possessables, tracks, sections, and keys. When I test in the editor, CreatePossessable() returns the FGuid of the created possessable as expected. But when I cook and package the project for Windows, the same function returns an invalid FGuid every time. I’m logging the level sequence to confirm it’s valid, so that’s not the issue.

Am I using the right function for this? Is this a bug in Unreal, or is this functionality blocked in builds for some reason?

I have the same problem. Did you manage to solve it?