Dependent Dropdowns, Options Not Returned

Hello! I'm trying to create multi-level dependent dropdowns using this plugin: https://github.com/kartik-v/dependent-dropdown but the options for the second selection are not showing up. Here is my code:

The View

<div class="form-group col-md-4">
    <label for="country_name">Country</label>
    <select class="form-control" name="country_name" id="countrySelector{{ $memberprofile->id }}">
        <option></option>
            @foreach( $countries as $country)
                <option value="{{ $country->id }}">{{ $country->name }}</option>
            @endforeach
    </select>
</div>
<div class="form-group col-md-4">
    <label for="region_name">Region</label>
    <select class="form-control" name="region_name" id="regionSelector{{ $memberprofile->id }}">
    </select>
</div>

JQuery script

// Region Selector
$("#regionSelector{{ $memberprofile->id }}").depdrop({
    depends: ['countrySelector{{ $memberprofile->id }}'],
    url: '{{ URL::route('regionselect') }}'        
});

Route

Route::get('/regionselect', ['as' => 'regionselect', 'uses' => 'User\MemberProfileFormController@regionSelector']);

Controller

public function regionSelector(Request $request)
{
    $childregions = ""; // define output variable   
    $countryname = 'Philippines';
    $country = Country::where('name','=', $countryname)->first();
    $countryid = $country->id;
            
    $regions = Region::where('country_id', '=', $countryid)->get();
                    
    return Response::json(['output'=>$regions, 'selected'=>'']);
}

When I load the route {{ URL::route('regionselect') }} in the browser, the region options are being returned correctly but in the actual form the regions are not returned. It just says "Loading...".

How do I properly return the options for the region selection? Thank you for the help.