Complex sentence: In 2010, Tenorio explained that from that point he used Tenorio as his surname, and he did not realize that his legal surname was still "Waddey" until he applied for a U.S. passport to visit Japan twenty years after middle school.
Split into simpler sentences: In 2010, Tenorio explained that from that point he used Tenorio as his surname. Tenorio stated that he did not realize that his full legal name was still "Waddey" until he applied for a U.S. passport to visit Japan twenty years after middle school.