Slide In conflicts with DoubleClick for Publishers?

I'm working on a client site, and got Slide In working great on a single post. But when we enabled a DoubleClick (DFP) popup ad on the site, Slide-In started showing a full-height panel on the right side of the page, pulling in (seemingly) random posts. That is, in the slide-in DIV itself, an entire blog post was displaying, which is why the slide-in ended up being full height. (Pic attached.) This happened on the home page, where I was NOT displaying my Slide-In.

I originally had the Global Settings configured to display Slide-Ins when someone reached the 33% mark on a page. I tried changing that do look for a div name instead (one that I'm not using anywhere on the site), but the div still displays.

Are there any known conflicts between Slide-In and DFP?