Elizabeth and Kathryn Girtler are healthy 9-year-old twin girls. But that wasn’t always the case. Friday night, at a gala event for Be The Match, a Minneapolis-based nonprofit organization that matches patients with bone marrow and umbilical cord blood transplants, the Girtler girls finally met the man who changed and saved their lives: Ingo Gruda. The girls – the whole family – said thank you. “Saying thank you isn’t enough,” said Michelle Girtler, the girls’ mother. “It’s like a cliché. We said, ‘You are forever our hero.’” For his part, Girtler said, Gruda told the girls they were now a…