供应商文件夹中的CodeIgniter控制器

I am using CodeIgniter 3 and the Rest-Server add-on. I've had some luck with getting the libraries to work (using AutoLoad config). However, I can't access the controllers. Is it possible to access the demonstration controllers as they sit in the vendor folder or do I have to move the contents of the vendor controller and view folders into the regular application folder?

I've indicated the controller I'm trying to access below.

Current structure:

Site Root
|
|-application
|-bin
|-public
|  |
|  \index.php
-vendor
 |
 |-chriskacerguis
 |
 | -codeigniter-restserver
 |  |
 |  |-application
 |  | |
 |  | |-config
 |  | |-controllers
 |  | | |
 |  | | |-api
 |  | | |-index.html
 |  | | |-Rest_Server.php (Controller I want to access)
 |  | | \-Welcome.php
 |  | |
 |  | |-helpers
 |  | |-language
 |  | |-libraries
 |  | |-migrations
 |  | \-views
 |  |-documentation
 |  \-LICENSE
 |-codeigniter
 |-composer
 |-mikey179
 \-autoload.php