It depends on just where she was injured and I've never seen either a Confederate or Union survey report on her. Much of the damage to the southern boats came from crushing the coal barges the Indianola was using for protection. Raising her involved two issues: temporary patching and pumping. I've never read that the Confederates had access to high volume steam pumps until the capture of the Champion up Red River in 1864. From an engineering point of view the Indianola wasn't much of an ironclad to start with. What she had to offer was machinery, plating and a number of the more hard to manufacture components that were almost unobtainable with the fall of New Orleans. Her guns were of great interest to both sides. As for the Confederate "second" scuttling. Again, it depends on what that used and where. My guess is that they attempted to destroy the casement and part of the machinery. The latter really wasn't a big issue if the Union had open access to the site and free routes to their repair stations. A raised crippled Indianola could have been towed to an area where she could be repaired. The clinker was her location, between Vicksburg and Port Hudson. The Union really couldn't do anything with her until one or both fell. After they fell, ironclads were much less important as there were few targets on the rivers left worth using them against. For the attrition war on the rivers, the ironclads were expensive overkill and not used a great deal. It was the timberclads, tinclads and transports that became the priority.