MySQL denies access only to laravel

For some reason, MySQL won't connect for one specific webapp. It will connect from the CLI, Sequel Pro (like Mysql Workbench), even a webapp hosted in a sibling directory (~/projects/iwork/, ~/projects/idontwork).

The only difference I can see is that the broken one is a laravel instance.

My .env:

DB_CONNECTION=mysql
DB_HOST=localhost
DB_PORT=3306
DB_DATABASE=idontwork_db
DB_USERNAME=dev
DB_PASSWORD=password

The error:

SQLSTATE[HY000] [1045] Access denied for user 'dev'@'localhost' (using password: YES) (SQL: select * from `instances` limit 1)

My config/database.php (this is unchanged from laravel's default):

'mysql' => [
    'driver' => 'mysql',
    'host' => env('DB_HOST', 'localhost'),
    'port' => env('DB_PORT', '3306'),
    'database' => env('DB_DATABASE', 'forge'),
    'username' => env('DB_USERNAME', 'forge'),
    'password' => env('DB_PASSWORD', ''),
    'charset' => 'utf8',
    'collation' => 'utf8_unicode_ci',
    'prefix' => '',
    'strict' => false,
    'engine' => null,
],

The dump of config('database.connections.mysql') as requested:

array:11 [▼
  "driver" => "mysql"
  "host" => "localhost"
  "port" => "3306"
  "database" => "idontwork_db"
  "username" => "dev"
  "password" => "nottherightpassword"
  "charset" => "utf8"
  "collation" => "utf8_unicode_ci"
  "prefix" => ""
  "strict" => false
  "engine" => null
]

The sibling webapp that works:

$DB_HOST = 'localhost';
$DB_NAME = 'iwork_db';
$DB_USER = 'dev';
$DB_PASS = 'password';

$dbc = new PDO('mysql:host=' . $DB_HOST . ';dbname=' . $DB_NAME, $DB_USER, $DB_PASS);
$dbc->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

So obviously one is trying to connect via Laravel and the other is native PDO, but I can't see any reason this should make a difference.

Things I've done:

• Composer and NPM have both installed their packages.
• I tried 127.0.0.1 and localhost.
• I've ensured the credentials are valid (like I said, I can get to idontwork_db from the CLI and Sequel Pro)
• Everything I've found on google seems to think I'm running out of connections, but this does not appear to be the case.

At this point I legitimately have no idea what is broken or how to troubleshoot it. Any assistance would be appreciated.

via Chebli Mohamed