You dont actually need to have a LP, all you need to describe is your plan to monetize it. Something along the lines of,
“I don’t have a landing page yet, i plan to use the existing landing page or create a new one. The traffic source will come from social networks like instagram, which i am also going to create a page for it, and the traffic will go to my landing page content locker.”
Also, register in cpaelites, and post in their thread you will most likely get approved easily.