Actually, Dallas was counting on Raghib Ismail not going to the Canadian Football League that year. Jimmy really didn't think he'd do it, but he did. At that point, Johnson had made the mistake of already trading for the #1 overall pick, when Ismail was the only true talent worthy of going #1 overall. Once Ismail was out of the picture, Jimmy was stuck with the first pick and in order to save face I remember him talking about controlling the draft, etc.
Maryland was a nice player, but in no way was he worth the first overall pick. There really wasn't anyone worth that choice one Ismail chose the CFL.