I also tried this but getting Call to undefined method Myth\Auth\Authentication\LocalAuthenticator::useModel() error.

For the second case, you mistyped userModel.

I'm confused by what you're trying to do in the first comment, though. Wouldn't it be enough to use groups/roles and restrict who can see it based on that?

There is a typo in the documentation itself. https://github.com/lonnieezell/myth-auth/blob/develop/docs/authentication.md#user-content-attaching-the-user-model

Also, method userModel or useModel doesn't exist in the Services class instead there are two methods setUserModel and setLoginModel. I tried these methods to load my modified models that contain updated table names but it's still using the default model provided by this library.

$this->auth = Services::authentication("local",new UserModel(), new LoginModel(),true);

$this->auth = Services::authentication();
$this->auth->setUserModel(new UserModel());
$this->auth->setLoginModel(new UserModel());

both codes returning same results

Didn't think about groups/roles I think I am going to use this approach.