Thanks for reaching out, and I am sorry to hear about this trouble you are having with your workflow being overwritten in Lucidchart.
Can you please make sure that the page with the simplified version is not a master page? When you use a master page, changes you make to it will automatically push to the other pages of your document.
If this does not help, please fill out a contact support form and include the URL to your document so I can take a closer look. Thanks!