Preload page cache not working

Everything is working great, except pre-loading, which is not working at all.

I have wp-cron disabled in wp-config, and have a real cron job setup to fire the cron job. I tested the cron job with scheduled posts, and it IS working, but nothing is being added to wp-content/cache/page_enhanced unless I go to a page manually.

The sitemap url is set to the sitemap from WordPress SEO:
https://www.thompsonsportinggoods.com/sitemap_index.xml

Any idea what could be preventing the cache from priming? Is there any way to set up a cron job specifically for preloading the cache?

https://ww.wp.xz.cn/plugins/w3-total-cache/