Absolutely not. A check for the final wages should have been included in the letter.
This answer is a general interpretation of the law and is not fact specific to your case. Likewise it does not create an attorney-client relationship. You should seek an attorney for a review of your specific facts and documents. http://www.johnphillipslaw.com
It does not matter how the notice of termination was conveyed. It could have been done by carrier pigeon - the legal obligation to pay all earned wages on the effective day of termination remains the same. Waiting-time penalties now apply.
They say you get what you pay for, and this response is free, so take it for what it is worth. This is my opinion based on very limited information. My opinion should not be taken as legal advice. For true advice, we would require a confidential consultation where I would ask you questions and get your complete story. This is a public forum, so remember, nothing here is confidential. Nor am I your attorney. I do not know who you are and you have not hired me to provide any legal service. To do so would require us to meet and sign written retainer agreement. My responses are intended for general information only.