Thanks for the detailed reply! You sound very familiar with

the divorce law. Do you mind telling me if you are an attorney or the related profession? I also have other questions for you:

(1)My LG and his Ex-wife's friends instead of attorney were the representatives to do the divorce. Is this fine with USCIS?

(2)Do you knwo why USCIS requested the Booklet if the notorized divorce certificate is good?

Greatly appreciated!