I'm somewhat new to Google Analytics, and I'm trying to track all conversions that are assisted by a particular landing page, because I don't expect an instant purchase. I have e-commerce tracking set up.

Due to the constraints of the associated ad campaign, I can't include the source/medium code in the url when people go to the landing page, and all of my traffic to the landing page is likely to be direct, so I'm not sure how to tell Multi-Channel marketing that it's a significant page. I know how to add events to a page, but I'm still figuring out what they can and cannot do. Would creating a redirect from the landing url to an identical url+source/medium code work? Any advice on how to accomplish this would be greatly appreciated.

Tracking the final sale conversion is not the issue. Ecommerce reporting is functioning just fine on the site. I just want to report the landing page as an assist, whenever it shows up in the funnel, and I need to be able to do that across multiple visits.