Given the brevity of the door remaining open, the Enterprise would have to of been charging at the door prior to Scotty and Geordi opening it. If they had timed it wrong, the Enterprise could conceivably have collided with the closed (or never opened) door.
Better the way they ended up doing things.
Besides would the Jenolan have been worth the time and energy of being towed to where ever for repairs? It was a century old and badly damaged.