Honestly at this point, I'd say screw it. Take it down for 6 months, rebuild all the trains, make any modifications necessary to the control system and brake runs, and open it.
Then wait for the next thing to go wrong...
That's what I would say as well, but they just can't afford the hit it would make on the park's overall operations, especially at this point in the year. They may be able to handle it better over the spring break season next year if the train rebuild would take more than 3 months, but I still don't see it happening. They'll take the hit with the sporadic extended downtimes and operational changes over closing the ride completely for a few months.