It depends what the waiver of service said. Talk to a lawyer in person who can look at the relevant documents and advise you.
This answer DOES NOT establish an attorney-client relationship. This answer is based on the limited information provided and is not intended to be conclusive advice. There are likely other factors that might influence or change the advice after a more lengthy consultation.
As stated by some of the other attorneys answering this question, it depends on the terms of the waiver. i would recommend that you have the waiver reviewed by an attorney. Some waiver's will state that the party executing the waiver is waiving his right to sign the final order whereas some will specifically state that the signing party is not waiving his right to sign final orders, receive notice of hearings, etc.