Using js crud library with checklist_dependency field type to manipulate additional dependencies

[vpoile]

I am using the checklist_dependency question type in the User CRUD controller for my platform, I need to add a dependent field if users belong to 1 or more of the roles, how do I target that field in the javascript crud library. I've tried the multiple methods of targetting the fields and nothing seems to work. Can anyone point out how I should be doing this.

1. This method seems to select the roles field but never triggers an onchange event, I think its actually selecting a hidden field related to the checklist grouping but because they are hidden not radio/checkbox type it doesn't seem to function as normal.

crud.field('roles').onChange(function(field){
    //show a related question if specific roles are checked
    console.log(field.value);
}).change();

2. This method fails to select the user_role_permission group object I assume its outside the scope of the crud js library
   Select top level and get child element:

crud.field('user_role_permission').subfield('roles').onChange(function(field) {
    //show a related question if specific roles are checked
    console.log(field.value);
}).change();

Gives the following error:

CrudField error! Could not select WRAPPER for "user_role_permission"
CrudField error! Could not select INPUT for "user_role_permission"

From the Controllers\UserCrudController.php

[
                // two interconnected entities
                'label'             => trans('backpack::permissionmanager.user_role_permission'),
                'field_unique_name' => 'user_role_permission',
                'type'              => 'checklist_dependency',
                'name'              => ['roles', 'permissions'],
                'subfields'         => [
                    'primary' => [
                        'label'            => trans('backpack::permissionmanager.roles'),
                        'name'             => 'roles', // the method that defines the relationship in your Model
                        'entity'           => 'roles', // the method that defines the relationship in your Model
                        'entity_secondary' => 'permissions', // the method that defines the relationship in your Model
                        'attribute'        => 'name', // foreign key attribute that is shown to user
                        'model'            => config('permission.models.role'), // foreign key model
                        'pivot'            => true, // on create&update, do you need to add/delete pivot table entries?]
                        'number_columns'   => 3, //can be 1,2,3,4,6
                    ],
                    'secondary' => [
                        'label'          => mb_ucfirst(trans('backpack::permissionmanager.permission_plural')),
                        'name'           => 'permissions', // the method that defines the relationship in your Model
                        'entity'         => 'permissions', // the method that defines the relationship in your Model
                        'entity_primary' => 'roles', // the method that defines the relationship in your Model
                        'attribute'      => 'name', // foreign key attribute that is shown to user
                        'model'          => config('permission.models.permission'), // foreign key model
                        'pivot'          => true, // on create&update, do you need to add/delete pivot table entries?]
                        'number_columns' => 3, //can be 1,2,3,4,6
                    ],
                ],
            ],

Any assistance is gratefully received.