Here are my thoughts:
(1) Good luck getting any response or help from Yahoo. Last year, we had a mystery team that hid his/her email address (and never did anything in the league after the autodraft) and Yahoo did nothing to help recify the situation or switch ownership to another owner. Never even returned a phone call or email.
(2) This league member of yours is either stupid or considers your league to be a joke. That's the only explanation for doing something as monumentally stupid as posting falso info. Therefore, I would not go out of my way to help him, because there is nothing to say he won't keep acting like this. Your league is probably better off without his participation.
(3) This is his problem, not yours and certainly none of the other league members. Therefore, any option involving any inconvenience to any other league members, like another draft (unless all of you ware VERY close friends), should not be considered.
(4) This guy's stupidity doesn't absolve him of his obligations. If money is on the line, then he still owes his fee. It will teach him to use his brain next time.
"One of the teams represents truth, justice, the American way, and underdogs everywhere. The other represents George Steinbrenner!" - U.S. News and World Reports columnist John Leo on the difference between the Mets and the Yankees.