PHP: Issue with class loading when running 'codeception run wpunit' - php

Question

I recently switched autoload in composer.json from classlist to psr-4. Then in terminal I ran vendor/bin/composer dump-autoload in the project root, which is a plugin directory.
My autoload settings:
"autoload": {
"psr-4": { "A\\" : "classes/A" }
}
There is only 1 class in ./classes/A so it was a concern when the console said it loaded 545 classes. I double checked that I was in the right (plugin) folder instead of the wordpress root.
It appears composer is recursively loading every wordpress class starting from 3 levels below. I get a list of errors, here are a few of the top ones.
owner#G700:/var/www/html/wptest2/wp-content/plugins/fvc$ vendor/bin/codecept run wpunit
Codeception PHP Testing Framework v2.5.6
Powered by PHPUnit 7.5.10 by Sebastian Bergmann and contributors.
Running with seed:
PHP Warning: call_user_func_array() expects parameter 1 to be a valid callback, class 'Utilities' not found in /var/www/html/wptest2/wp-includes/class-wp-hook.php on line 286
PHP Stack trace:
PHP 1. {main}() /var/www/html/wptest2/wp-content/plugins/fvc/vendor/lucatume/wp-browser/src/includes/isolated-install.php:0
PHP 2. activate_plugin() /var/www/html/wptest2/wp-content/plugins/fvc/vendor/lucatume/wp-browser/src/includes/isolated-install.php:210
PHP 3. do_action() /var/www/html/wptest2/wp-admin/includes/plugin.php:660
PHP 4. WP_Hook->do_action() /var/www/html/wptest2/wp-includes/plugin.php:465
PHP 5. WP_Hook->apply_filters() /var/www/html/wptest2/wp-includes/class-wp-hook.php:310
PHP Warning: require_once(../../vendor/autoload.php): failed to open stream: No such file or directory in /var/www/html/wptest2/wp-content/plugins/fvc/tests/wpunit/T1Test.php on line 2
PHP Stack trace:
PHP 1. {main}() /var/www/html/wptest2/wp-content/plugins/fvc/vendor/codeception/codeception/codecept:0
PHP 2. Codeception\Application->run() /var/www/html/wptest2/wp-content/plugins/fvc/vendor/codeception/codeception/codecept:43
PHP 3. Codeception\Application->run() /var/www/html/wptest2/wp-content/plugins/fvc/vendor/codeception/codeception/src/Codeception/Application.php:108
This is an autoload error right? Any idea how I can fix this?
In case this might be something else I am including the test file I am running. This is the only test file that should run with the command vendor/bin/codecept run wpunit
<?php
require_once("../../vendor/autoload.php");
require_once ('../../classes/A/T1.php');
class T1Test extends \Codeception\TestCase\WPTestCase
{
public function testAdd() {
$t1 = new \T1();
$this->assertEquals(1, 1);
$sum = $t1->add(5, 2);
$this->assertEquals(7, $sum, "didn't sum");
}
}