[Stephen]

The Falcon was always breaking down and falling apart. They usually foxed it with a bit of welding or snacking the console.

Star Wars tech is not meant to be realistic or anything.

They managed to seal the cockpit and patch up the engines enough to limp to the planned planet. Without Hyperspace travel. So I see nothing wrong in the way the ship was repaired. It was a patch job just to enable to to have basic flight.