UStaticMesh::BuildFromMeshDescriptions does not create complex collision in packaged game

I’m trying to create a new mesh using FBX in runtime (to support player-imported models). When running the game in the editor, both simple and complex collisions are fine. However, after packaging, only simple collisions work. Complex collisions are not there at all.

I have also set up the params correctly, I believe. In UStaticMesh::FBuildMeshDescriptionsParams, I’ve set bBuildSimpleCollision = true and bAllowCpuAccess = true.

Is there something I’m missing?