Evaluators are set up by provider account rather than to as specific program. Therefore, once an evaluator has been set up in your account, they will continue to show for programs in the future unless they have been disabled by you. You will be able to see past evaluators in your list of possible evaluators to assign to an application.
If that evaluator does not remember their password, they can go to the login page at app.smarterselect.com/login and click the "Forgot Password" link.
As a provider, you can also send the evaluator a password reset email by clicking on "Reset" in the "Password" column of your People table. However, it is best practice to notify the evaluator that you will be doing this beforehand.