Oct 31 is a holiday in the US - thank you for your patience.
It looks like there is something causing this problem in one of your content types. Other than forums, which content types are active? Try disabling the other content types one at a time to determine which one is causing the problem. Once we know that, we can focus on the specific content that's causing it.
For example, it might be something in the News content - or the way it's been tapped (converting dynamic URLs from .php to .html). I noticed in the HTML version of the sitemap that it doesn't display content after forums.
Also, were any modifications made to any of the content types in modules/Sitemap/content? Are there any extra files in that directory that aren't in the nukeSEO distribution?
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