Do you have a heavy-duty utility like Disk Warrior, TechTool Pro, or Drive Genius? They are more powerful than Disk Utility.
No. Do you think that would make a difference at this point? That sounded facetious, but I didn't mean it that way.
I can't give a definitive answer, but if the problem can be fixed, one of those utilities is more likely to fix it than Disk Utility. In particular, I'm a fan of Disk Warrior.
Speaking from personal experience, a few years ago my daughter did something really bad to her MacBook. I have no idea what she did but it ended up with her machine grinding away for at least 24 hours and no apparent advance.
Although it sounded to me like there was no hope, I asked her to shut the machine off until I could come over with Disk Warrior. It took Disk Warrior about two hours but, in the end, her machine was back to working as normal.
Whether you were to go for Tech Tool Pro or Disk Warrior, it seems to me you're going to have to decide if you want to gamble 100 bucks that might keep you from spending a couple of grand.