Can working your abs cause you to get hernias?

Not cause. Physical activity does not cause hernia, but it can make them larger and appear. Usually hernias are due to a congenital weakness or after surgery.
Yes or no. If you have potential weak area at hernial site, or a small hernia you did not notice ( to be pointed out by your physician ), or a weak scar from previous surgery you may develop hernia. If you do not have those , not much chance of getting a hernia, go for abdominal work out.