That should be the xact code you have in your controller. The route model binding in the method parameter is equivalent to the find. You then just need to include $profile->load('photo.review');
If that doesn't work, it might be worth creating an API resource for photo as well. Where you include the review relationship if it has been loaded.
'photo' => PhotoResource::collection($this->photo),
So in your PhotoResource, you would have a line like this:
'review' => $this->whenLoaded('review')
That way, when you normally view photos without loading the review, it won't be included.