How to use Dompdf with Entity Print without composer? I'm trying to make Entity Print work but I'm having issues with configuring the module.

The project I'm working on is two years old and for some reasons, I can't use composer and the module folder is at the project's root. The modules that have been created manually are in modules/custom, those downloaded are in modules/contrib

I downloaded and unzipped dompdf 0.8.1 in my vendor directory, and did the same in modules/contrib for Entity Print.

However, after the installation, when I try to make the module work, I get the message 


  "Dompdf is not available because it is not configured. Please install with: composer require "dompdf/dompdf 0.8.0".


I have the choice between TCPDF (v1) that gets a PHP error when activated, that makes me need to reinstall the module if I want to get back to the configuration page, and Php Wkhtmltopdf that can't reach the server X even though I installed every related libraries I could find.

One coworker told me that he managed to make Entity Print work with DomPDF, but he couldn't remember how, even though it had something to do with the autoload.

I can't manage to make the couple solutions I found, and I don't really know what I'm looking for.

Please tell me if you need to see a file's content, I don't really know what I can show you for now.

Thank you in advance
I have been using the same module and was able to get it setup with Dompdf. Here are the steps in detail I used.

Summarized steps:


composer require drupal/entity_print (this automatically downloads the dompdf dependency for me)
On the content type, I enabled the custom display setting of PDF
Followed steps in "From your theme" to create the print.css and twig templates
composer require dompdf/dompdf (in case #1 doesn't download it)


Alternative: Ludwig module