Adding android apps to folders on fully managed devices, using intune

Question

I have been trying to add android apps to folders on the managed home screen, using MS Launcher (com.microsoft.launcher) on fully managed devices. I believe the functionality is there, using the JSON key com.microsoft.launcher.folder.custom However this is not in the MS literature for this key. It is possible in the Managed Home Screen app (com.microsoft.launcher.enterprise), but we are using Fully Managed devices, not Dedicated devices.

I have tried the below JSON to no avail :( Has anyone managed to do this on Fully Managed devices? I believe the function is there.

{
    "kind": "androidenterprise#managedConfiguration",
    "productId": "app:com.microsoft.launcher",
    "managedProperty": [
{ 
            "key": "com.microsoft.launcher.Folder.Style",
             "valueBundleArray": [
                {
                    "managedProperty": [
                        {
                            "key": "foldershape",
                            "valueString": "Squircle"
                        },
                        {
                            "key": "OpenFullScreen",
                            "valueString": "True"
                        }
                    ]
                }
            ]
        },
        {
            "key": "com.microsoft.launcher.HomeScreen.folder",
            "valueBundleArray": [
                {
                    "managedProperty": [
                        {
                            "key": "custom",
                            "valueString": "Microsoft"
                        },
                        {
                            "key": "applications",
                            "valueBundleArray": [
                                {
                                    "managedProperty": [
                                        {
                                            "key": "package",
                                            "valueString": "com.microsoft.emmx"
                                        }
                                    ]
                                },
                                {
                                    "managedProperty": [
                                        {
                                            "key": "package",
                                            "valueString": "com.microsoft.bing"
                                        }
                                    ]
                                },
                                {
                                    "managedProperty": [
                                        {
                                            "key": "link",
                                            "valueString": "https://microsoft.com/"
                                        }
                                    ]
                                }
                            ]
                        }
                    ]
                },
     ]
}