When using the duplicator plugin on WordPress to install a cloned site, why am I getting an install error stating 'wp-config.php is empty'?

So I have been tasked with cloning a site using duplicator and it is my first time doing this. I began by creating a new directory, uploading the duplicator zip and install file from the site I wanted to clone and then running it, which resulted in "wp-config.php file is empty".

I then deleted all of the old WordPress files, rendering the website essentially entirely empty and tried again with the same error. I then uploaded the old wp-config.php and yet again, have got the same error.

When installing the duplicator files, I run everything on default settings and install the zip/install.php files from a subdirectory called installer. The trace is below.

'#0 /home/"website name"/public_html/installer/dup-installer/views/view.s3.php(315): WPConfigTransformer->exists('constant', 'WP_CACHE')
#1 /home/"website name"/public_html/installer/dup-installer/main.installer.php(356): require_once('/home/"website name"/...')
#2 {main}'

And this is from the installer log

START ZIP FILE EXTRACTION STANDARD >>> 
FILE CORE EXTRACION ERROR: wp-includes/class-smtp.php
FILE CORE EXTRACION ERROR: wp-includes/link-template.php
FILE EXTRACION ERROR: wp-includes/class-wp-fatal-error-handler.php
FILE EXTRACION ERROR: wp-includes/class-wp-recovery-mode.php
FILE CORE EXTRACION ERROR: wp-includes/kses.php
FILE CORE EXTRACION ERROR: wp-includes/general-template.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-simplepie-file.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-comment.php
FILE CORE EXTRACION ERROR: wp-includes/nav-menu-template.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-image-editor.php
FILE EXTRACION ERROR: wp-includes/class-wp-recovery-mode-cookie-service.php
FILE EXTRACION ERROR: wp-includes/ms-site.php
FILE EXTRACION ERROR: wp-includes/class-wp-paused-extensions-storage.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-oembed-controller.php
FILE CORE EXTRACION ERROR: wp-includes/option.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-widget-factory.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-http-encoding.php
FILE EXTRACION ERROR: wp-includes/ms-network.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-block-type-registry.php
FILE CORE EXTRACION ERROR: wp-includes/registration-functions.php
FILE CORE EXTRACION ERROR: wp-includes/registration.php
FILE CORE EXTRACION ERROR: wp-includes/blocks.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-role.php
FILE CORE EXTRACION ERROR: wp-includes/class-walker-page-dropdown.php
FILE CORE EXTRACION ERROR: wp-includes/class.wp-dependencies.php
FILE CORE EXTRACION ERROR: wp-includes/update.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-query.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-list-util.php
FILE CORE EXTRACION ERROR: wp-includes/atomlib.php
FILE CORE EXTRACION ERROR: wp-includes/functions.php
FILE CORE EXTRACION ERROR: wp-includes/capabilities.php
FILE CORE EXTRACION ERROR: wp-includes/cron.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-taxonomy.php
FILE CORE EXTRACION ERROR: wp-includes/class-wp-http-proxy.php
FILE CORE EXTRACION ERROR: wp-

Any help at all would be greatly appreciated!