I don’t see a place to mark this as answered, but I problem solved with a buddy of mine, and made some changes to WP Settings > Permalinks. After changing them from month/date to default, and back. The issue cleared up. I have no idea why, but I guess it wasn’t a theme issue, but a WP one. No need to follow up.

Also tried switching to the parent theme (eliminating my child theme) and I still am getting the 404 error. So, it’s not my child theme, which is mainly some css changes.