Relationship box won't show up below costom fields

I have a relationship defined that works as I want, except it shows up below the custom fields on one side of the relationship, but not on the other side.

I have tried to put the context = normal in different places, and it just doesn't move away from the sidebar.

add_action('mb_relationships_init', function () {
    MB_Relationships_API::register([
        'id'   => 'djs_to_events',
        'from' => array(
            'post_type' => 'tmd_dj',
            'admin_columns' => array(
                'position'   => 'after title',
                'title'      => 'Events',
            ),
            'empty_message' => 'No DJs connected',
            'context' => 'normal',

            'meta_box' => array(
                'id' => 'event_selection',
                'name' => 'Events',
                'title' => 'Events this DJ played at',
                'context' => 'normal',
                'class'   => 'event_selection',
            ),
            'field'         => array(
                'context' => 'advanced',
                'name'        => 'DJs playing in this event',
                'label_description' => '',
                'placeholder' => 'Select DJs',
                'add_button'  => 'Add another Event',
            ),

        ),
        'to'   => array(
            'post_type' => 'tmd_event',
            'empty_message' => 'No events connected',

            'admin_columns' => array(
                'position'   => 'after title',
                'title'      => 'DJs',
            ),
            'context' => 'advanced',
            'meta_box' => array(
                'id' => 'dj_selection',
                'name' => 'DJs',
                'title' => 'Select DJs',
                'context' => 'advanced',
                'class'   => 'dj_selection',
            ),
            'field'         => array(
                'context' => 'advanced',
                'name'              => 'This DJs played at the linked events',
                'label_description' => '',
                'desc'              => 'Not all events are usually linked, but we try our best.',
                'add_button'        => 'Link with another event',
            ),

        ),

    ]);
});