Update Failed error with WP and cPanel

Hi

A client of mine uses cPanel to manage their PHP and wordpress software, all that stuff. There’s a calculator tool on this Tools page, and the code of the tool can be found on the cPanel file directory. However, the unnecessary text around the page is stored directly in the WordPress admin side where you can edit the Tools page, and whenever I try to edit that text in WordPress, it fails with an “Updating failed” message. The text is not in cPanel, and I can’t delete or update that page from WP at all, so I’m not sure of exactly what I should do.

The page I need help with: [log in to see the link]