Austin played collegiate lacrosse at Lynchburg College under Coach Steve Koudelka. He was named a captain his senior year. Lynchburg made an appearance in the National Championship in his junior year when he was named 1st team All-American and broke the NCAA record for goals scored in a season. Stewart is very passionate about the game and has coached various levels of lacrosse for years. He currently works as Director of Operations for Millon Lacrosse.