How to convert file path to treeUri

In my application i have a regular Settings, where user can choose a video directory on his android device, and videos found in that directory will play at some point in the application. Now, when user himself is doing that via Preferences, i am opening ACTION_OPEN_DOCUMENT_TREE, and Uri returned is treeUri, that i am later using in my Video Activity with DocumentsContract.buildChildDocumentsUriUsingTree. This part is completely fine, it's working and all is OK.

However, since this application is going to be used in enterprises, i have a request, that IT department can submit an external xml file that i am completely controlling in application external directory, with all options that you as a user can set in the application itself, and if that file exists, those options need to be implemented in SharedPreferences. I got all settings to be implemented from that external xml file, apart that video directory. I was thinking that user can give regular path in the xml, like <setting key="video_folder">/sdcard/Movies</setting>, and then i parse that in the application, get treeUri from path, and save it in SharedPreferences for later use. Any ideas if this is doable, or this should have some other approach?
I've tried this method below:

public static Uri[] getSafUris (Context context, File file) {
Uri[] uri = new Uri[2];
String scheme = "content";
String authority = "com.android.externalstorage.documents";
// Separate each element of the File path
// File format: "/storage/XXXX-XXXX/sub-folder1/sub-folder2..../filename"
// (XXXX-XXXX is external removable number
String[] ele = file.getPath().split(File.separator);
//  ele[0] = not used (empty)
//  ele[1] = not used (storage name)
//  ele[2] = storage number
//  ele[3 to (n-1)] = folders
//  ele[n] = file name
// Construct folders strings using SAF format
StringBuilder folders = new StringBuilder();
if (ele.length > 4) {
folders.append(ele[3]);
for (int i = 4; i < ele.length - 1; ++i) folders.append("%2F").append(ele[i]);
}
String common = ele[2] + "%3A" + folders.toString();
// Construct TREE Uri
Uri.Builder builder = new Uri.Builder();
builder.scheme(scheme);
builder.authority(authority);
builder.encodedPath("/tree/" + common);
uri[0] = builder.build();
// Construct DOCUMENT Uri
builder = new Uri.Builder();
builder.scheme(scheme);
builder.authority(authority);
if (ele.length > 4) common = common + "%2F";
builder.encodedPath("/document/" + common + file.getName());
uri[1] = builder.build();
return uri;
}

but that gives me:

Permission Denial: reading com.android.externalstorage.ExternalStorageProvider uri content://com.android.externalstorage.documents/tree/Movies%3A/document/Movies%3A/children from pid=28318, uid=10157 requires that you obtain access using ACTION_OPEN_DOCUMENT or related APIs

I had to completely rearrange logic for playing videos, to read them from regular file:// uri's, in order to bypass SAF. In short, my question was, if you don't obtain tree URI from ACTION_OPEN_DOCUMENT, ACTION_OPEN_DOCUMENT_TREE, and similar API's, is there any way possible, to obtain a permission for such tree URI. As far as i could tell, that is not possible (not even with any kind of runtime permission presented to the user). If anyone else believes that there is such a possibility, please, let me know.