I don't use XML, or at least I haven't so far, though I'm sure I will eventually. But if you've managed to extract XML worksheets, won't Excel read them directly? Then you can assemble them into a new workbook.

Would you care to post the bad workbook here? If there's nothing confidential in it, I'd be interested in taking a look to see whether I notice a possibility for rescue that I haven't thought of yet.

And if nothing else works, I suggest you ask the XML question again, in a new thread so that someone else will pay attention to it. (Otherwise someone who knows the answer may glance at this and assume I'm helping you.)