Issue Accessing Parent Loop Object in Nested Custom Query Provider

I'm building a threaded comment system using custom query providers. I use Bricks Builder and the Query loop it provides. I created custom query types for parent comment and replies comment. Parent comments work fine, but I can't get replies to show in the nested loop.

Current Setup:

Hub Registry (working):

add_filter('bricks/setup/control_options', 'gna_register_query_types');
function gna_register_query_types($control_options) {
    $control_options['queryTypes']['gna_comments'] = 'Comments';
    $control_options['queryTypes']['gna_comment_replies'] = 'Comment Replies';
    return $control_options;
}

add_filter('bricks/query/run', 'gna_run_custom_query', 10, 2);
function gna_run_custom_query($results, $query_obj) {
    if ($query_obj->object_type === 'gna_comments') {
        $results = gna_comments_query_handler();
    }
    if ($query_obj->object_type === 'gna_comment_replies') {
        $results = gna_comment_replies_query_handler();
    }
    return $results;
}

Parent Handler (works):

function gna_comments_query_handler() {
    global $post;
    $post_id = $post->ID;
    
    $comments = get_comments([
        'post_id' => $post_id,
        'parent' => 0,
        'status' => 'approve',
    ]);
    
    return $formatted_array; // Returns parent comments successfully
}

Reply Handler (doesn't work):

function gna_comment_replies_query_handler() {
    // How do I get parent comment ID from outer loop?
    $loop_object = \Bricks\Query::get_loop_object(); // Returns null
    $parent_id = $loop_object['id'] ?? 0;
    
    return get_comments(['parent' => $parent_id]); // Always empty
}

Bricks Structure:

Container (Query: gna_comments) ✅ Works
└─ Container (Query: gna_comment_replies) ❌ No results

Question: How do I access the parent loop's data inside a nested custom query provider? \Bricks\Query::get_loop_object() returns null in the nested handler.

Is there a different method for custom query types versus native Posts queries?

Thanks for any help!