Some context: Supergirl is a fictional superhero appearing in American comic books published by DC Comics. The character was created by writer Otto Binder and designed by artist Al Plastino. Supergirl first appeared in a story published in Action Comics #252 (May 1959) titled "The Supergirl from Krypton". Kara Zor-El is the biological cousin of Kal-El (Superman).
After long-time Superman family editor Mort Weisinger retired in 1971, the character underwent revitalization under editor Joe Orlando and artist Mike Sekowsky. Wearing a series of new outfits, leaving her adopted foster home with the Danvers family, Linda goes on to San Francisco where she works for KSF-TV as a camera operator and develops a crush on her boss, Geoffrey Anderson. These stories introduced Supergirl's most memorable villain from this period: Lex Luthor's niece Nasthalthia, or Nasty. Nasty had made two appearances towards the end of Linda's college years, then pursued her to KSF-TV, trying to secure proof of her dual identity.  Supergirl starred in her first solo eponymous monthly series beginning in 1972 until October 1974, when her monthly title merged with Superman's Girl Friend, Lois Lane, and Superman's Pal Jimmy Olsen to produce a new title: then-highest DC selling series called The Superman Family, where she eventually became the steady lead story. Linda worked as a student advisor at New Athens Experimental School, before leaving for New York to follow a career in acting with daytime soap Secret Hearts.  In 1982 Supergirl received a second monthly solo series titled The Daring New Adventures of Supergirl, relocating the character to Chicago as Linda became a mature student of Psychology. Industry legend, and former DC Publisher, Carmine Infantino provided the pencilled art (Bob Oksner inked). With issue 13 the title was revamped, with a new costume design (sporting a red headband) and the title shortened to just Supergirl. The series ran until sudden cancellation in 1984, only two months before the character's debut in a big-budget Hollywood film starring Helen Slater.  In the Crisis on Infinite Earths (1985) the greatest heroes from Earth-One, Earth-Two, Earth-Four, Earth-S, and Earth-X join forces in order to defeat the Anti-Monitor. When Superman comes face to face with the Anti-Monitor and is knocked unconscious, Supergirl rushes to save him before he is killed. She is able to fight him off long enough for Dr. Light to carry her cousin to a safe distance, but is killed by the Anti-Monitor. A public memorial service for Supergirl takes place in Chicago, where Batgirl (Barbara Gordon) delivers the eulogy. In her remarks she states "Kara is a hero. She will not be forgotten." Superman then gives his late cousin burial by taking her corpse to Rokyn/New Krypton to Zor-El and Allura. A Superman issue the next month reveals that Kara had experienced a premonition about her own passing. However, when the universe is rebooted, the timeline is altered. Kara Zor-El and all memory of her is erased from existence.
did she ever get the proof needed to prove dual identy
A: 
Some context: Robert Lee "Bullet Bob" Hayes (December 20, 1942 - September 18, 2002) was an Olympic sprinter turned American football wide receiver in the National Football League for the Dallas Cowboys. An American track and field athlete, he was a two-sport stand-out in college in both track and football at Florida A&M University. He has one of the top 100 meter times by NFL players. Hayes was enshrined in the Dallas Cowboys Ring of Honor in 2001 and was selected for induction in the Pro Football Hall of Fame in January 2009.
Hayes was a highly recruited athlete, and accepted a football scholarship from Florida A&M University a historically black college, where he excelled in track & field.  He never lost a race in the 100 yard or 100 meter competitions, but mainstream schools of the area still did not invite him to their sanctioned meets. In 1962 the University of Miami invited him to a meet on their campus, where he tied the world record of 9.2 seconds in the 100-yard dash, which had been set by Frank Budd of Villanova University the previous year. He also was the first person to break six seconds in the 60 yard dash with his indoor world record of 5.9 seconds.  In 1963, although he never used a traditional sprinter form, he broke the 100-yard dash record with a time of 9.1, a mark that would not be broken for eleven years (until Ivory Crockett ran a 9.0 in 1974). That same year, Hayes set the world best for 200 meters (20.5 seconds, although the time was never ratified) and ran the 220 yard dash in a time of 20.6 seconds (while running into an eight mph wind). He was selected to represent the United States in the 1964 Summer Olympics in Tokyo. His football coach Jake Gaither was not very high on giving Hayes time to train, which caused then president Lyndon B. Johnson to call him in order to allow Hayes time off and to keep him healthy.  He was the AAU 100 yard dash champion three years running, from 1962-1964, and in 1964 was the NCAA champion in the 200 meter dash. He missed part of his senior year because of his Olympic bid for the Gold medal.  In 1976, he was inducted into the inaugural class of the Florida A&M University Sports Hall of Fame. In 1996, he was inducted into the Southern Intercollegiate Athletic Conference Hall of Fame. In 2011, he was inducted into the Black College Football Hall of Fame.
Did he win any meets?
A:
He never lost a race in the 100 yard or 100 meter competitions,