To be honest with you I think the dealer doesn't know what they are talking about. The latest recall requires them to remove the lock plate from the column lock so the wheel will not lock. If your wheel is locked it sounds like the lock plate is still in your car, so therefore I would venture to say the latest recall hasn't been done to your car. Perhaps some steering wheel lock recall has been done, but not the latest, because obviously you are still having a problem. Here is a copy of some info I found.
NHTSA Campaign Number: 04V060000
www.nhtsa.dot.gov
Manufacturer GENERAL MOTORS CORP.
Recall Date: 02/09/2004
Potential Number Of Units Affected: 126,624
Description STEERING:COLUMN LOCKING:ANTI-THEFT DEVICE
Summary ON CERTAIN PASSENGER VEHICLES EQUIPPED WITH ELECTRONIC COLUMN LOCK SYSTEMS (ECL), WHEN THE IGNITION SWITCH IS TURNED TO LOCK, THE ECL SYSTEM PREVENTS TURNING OF THE STEERING SYSTEM. WHEN THE VEHICLE IS STARTED, THE ECL UNLOCKS THE STEERING SYSTEM. THE VEHICLE IS DESIGNED SO THAT IF THE COLUMN FAILS TO UNLOCK WHEN THE VEHICLE IS STARTED AND THE CUSTOMER TRIES TO DRIVE, THE FUEL SUPPLY WILL BE SHUT OFF SO THAT THE VEHICLE CANNOT MOVE WHEN THE VEHICLE CANNOT BE STEERED. IF VOLTAGE AT THE POWERTRAIN CONTROL MODULE IS LOW OR INTERRUPTED, HOWEVER, THE FUEL SHUT OFF MAY NOT OCCUR AND THE VEHICLE CAN BE ACCELERATED WHILE THE STEERING SYSTEM IS LOCKED. ALSO WHEN THE CONTROL SYSTEM SHOWS THAT THE ECL IS UNLOCKED AND THE VEHICLE IS BEING DRIVEN, THE LOCK PIN LOCATION CAN VARY. DEPENDING ON THE LOCATION OF THE LOCK PLATE RELATIVE TO THE SWITCH TRANSITION POINT, THERE COULD THEN BE CONTACT BETWEEN THE LOCK PLATE AND PIN CAUSING THE STEERING TO LOCK WHILE DRIVING .
Consequence IF THIS OCCURS, A CRASH COULD OCCUR WITHOUT WARNING.
Remedy ON VEHICLES EQUIPPED WITH AN AUTOMATIC TRANSMISSION, THE DEALER WILL DISABLE THE STEERING COLUMN LOCK BY REMOVING THE COLUMN LOCK PLATE. WHEN THE IGNITION KEY IS REMOVED, THE TRANSMISSION SHIFTER WILL LOCK BUT THE STEERING COLUMN WILL NOT LOCK. ON VEHICLES EQUIPPED WITH A MANUAL TRANSMISSION, THE DEALER WILL REPROGRAM THE POWERTRAIN CONTROL MODULE, PERFORM A DIMENSIONAL CHECK OF THE COLUMN LOCK AND, IF NECESSARY, REPLACE THE LOCK PLATE. THE STEERING COLUMN ON THESE VEHICLES WILL CONTINUE TO LOCK WHEN THE KEY IS REMOVED. OWNER NOTIFICATION TO OWNERS OF 1997 VEHICLES EQUIPPED WITH AUTOMATIC TRANSMISSIONS BEGAN ON APRIL 26, 2004. OWNERS OF 1998 THROUGH 2004 VEHICLES (EXCEPT 1997-1998 MANUAL TRANSMISSION VEHICLES) WILL BE NOTIFIED BEGINNING ON AUGUST 2, 2004. THE REMAINING OWNERS (1997-1998 MANUAL TRANSMISSION VEHICLES) WILL BE NOTIFIED LATER IN 2004, WHEN PARTS ARE AVAILABLE.
OWNERS SHOULD CONTACT CHEVROLET AT 1-800-630-2438.
Now as you can see there is a phone number to call Chevrolet, I would do just that. Tell them your wheel is locked, it has been locked, and you are afraid it will lock while you are driving and you are in fear that someone will be hurt or killed, and if someone is killed you will have to sue GM and put your name on all their company logos. Call them up, tell them you want your car towed in and fixed and you don't want to pay for any part of this repair. This is a SAFETY RECALL and they are obligated to fix it free of charge.