I bought a brand new couch for $2600. There was a hole in the bottom that the furniture company tried to patch over and not tell us. Fraud?

Fraud requires that the misstatement or omission be deliberate and "material," which it is impossible to ascertain from your inquiry. Even if this non-disclosure isn't fraudulent, it may nevertheless be a breach of contract entitling you to a replacement or refund. Your personal attorney can advise you about this.