Drupal * on an older server – Composer required for contrib module

I am wondering if there are hints in the composer system code that will let me know how to install required libraries for the /project/get_linkedin_posts/ module. We asked this question more specifically in the module issues. I am guessing that somewhere within the composer code that is within the module there are directives for composer to install the libraries.

Currently, I have the “composer.json” file from the module. The require statement seems to be the reference for the library. I can find the library on GitHub from the documentation of the module. I have attempted to install this library under the libraries folder in the root of the site. Any suggestions of where I can find documentation on sidestepping composer for a manual installation?

  “name”: “drupal/get_linkedin_posts”,
  “type”: “drupal-module”,
  “description”: “Provides functionality for import posts from Linkedin page of Company in Drupal nodes.”,
  “license”: “GPL-2.0+”,
  “homepage”: “https://www.drupal.org/project/get_linkedin_posts“,
  “minimum-stability”: “dev”,
  “require”: {
    “league/oauth2-linkedin”: “^2.0”

Drupal version: 

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