Yes, you and your friend can proceed the way that you suggest. She does not need to sign that she translated it. She only needs to sign to certify that she is fluent in both languages and that the translation is a complete and accurate translation of the original document. It doesn't matter who actually did the work of translating it.
Your friend needs to be able to certify that he/she is fluent in both languages and that the translation is a full and accurate translation of the original.
J Charles Ferrari Eng & Nishimura 213.622.2255 The statement above is general in nature and does not constitute legal advice, as not all the facts are known. You should retain an attorney to review all the facts specific to your case in order to receive advise specific to your case. The statement above does not create an attorney/client relationship.