Data for NOT removing navigation on marketing page

We have been having some heated discussions lately. The marketing department wants to remove the top navigation from their marketing sell pages. (Marketing sell pages are basically VERY long web pages that sell a product.)

Their rational for doing this is they think it will increase conversions. I am against removing the navigation. The data (click maps) we have from past marketing sell pages shows that users are using the top navigation. Links in the top navigation are among the top 3 clicks on the page. I have shared this data with marketing. I have also shared that navigation reduces task time, provides a better user experience, and the task is perceived as easier. Hamburger Menus and Hidden Navigation Hurt UX Metrics

Does anyone have any data about navigations and conversions? Data about user experience and usability isn't helping, I need data specifically about conversions if I am to convince them their idea is not a good one.