Laravel Passport multi auth always falling back to my default guard - laravel-8

Question

I'm currently moving an app from Laravel/lumen 6 to Laravel/Lumen8.
Previously I was using this package https://github.com/sfelix-martins/passport-multiauth to handle multi auth.
Now that Laravel Passport is handling multiple auth natively I have switched to Passport 10.
I have updated my config/auth.php file with all my guards and providers
return [
'defaults' => [
'guard' => 'users',
'passwords' => 'users',
],
'guards' => [
'users' => [
'driver' => 'passport',
'provider' => 'users',
],
'dashboardUsers' => [
'driver' => 'passport',
'provider' => 'dashboardUsers',
],
'retailers' => [
'driver' => 'passport',
'provider' => 'retailers',
]
],
'providers' => [
'users' => [
'driver' => 'eloquent',
'model' => \App\User::class,
],
'dashboardUsers' => [
'driver' => 'eloquent',
'model' => \App\DashboardUser::class,
],
'retailers' => [
'driver' => 'eloquent',
'model' => \App\DashboardUser::class,
],
],
...
];
I'm having my defaults middlewares in boostrap/app.php like this:
$app->routeMiddleware([
'auth' => App\Http\Middleware\Authenticate::class,
'scopes' => \Laravel\Passport\Http\Middleware\CheckScopes::class,
'scope' => \Laravel\Passport\Http\Middleware\CheckForAnyScope::class,
]);
The Authenticate Middleware is the one defined in default Lumen package:
<?php
namespace App\Http\Middleware;
use Closure;
use Illuminate\Contracts\Auth\Factory as Auth;
use Illuminate\Auth\AuthenticationException;
class Authenticate
{
/**
* The authentication guard factory instance.
*
* #var \Illuminate\Contracts\Auth\Factory
*/
protected $auth;
/**
* Create a new middleware instance.
*
* #param \Illuminate\Contracts\Auth\Factory $auth
* #return void
*/
public function __construct(Auth $auth)
{
$this->auth = $auth;
}
/**
* Handle an incoming request.
*
* #param \Illuminate\Http\Request $request
* #param \Closure $next
* #param string|null $guard
* #return mixed
*/
public function handle($request, Closure $next, $guard = null)
{
if ($this->auth->guard($guard)->guest()) {
throw new AuthenticationException();
}
return $next($request);
}
}
If I use my default guard (users) everything is working fine. But if I try to use one of my 2 other guards like this :
$router->group(['middleware' => ['auth:dashboardUsers', 'scope:admin-retailers,manage-retailers']], function () use ($router) {
$router->get('/dashboard/retailers/getRetailers', 'RetailerController#getRetailersByUser');
});
The result is really weird since my guard seems to be correctly defined (dashboardUsers), but it's still falling back to my default provider (so my user can't be found of course).
The only fix I could find is to update my Authenticate middleware like this:
public function handle($request, Closure $next, $guard = null)
{
if ($this->auth->guard($guard)->guest()) {
throw new AuthenticationException();
}
config(['auth.guards.users.provider' => $guard]);
return $next($request);
}
This way I'm redefining my config to use the correct provider. But that feels hacky and I think I'm missing a point somewhere in my configuration. Since everything is defined in my auth.php file I shouldn't have to redefine my provider in my middleware.
Any idea what could be the problem?
Thanks for the help.