Did anyone found an answer for this? This post is 2yo but I have the same exact issue.
Hi Lucia,
For a more accurate report, most customers will create 2 channels; Email with Landing Page and Email without Landing Page. The statuses are different between the 2 with the ability to update success upon form fill-out. This allows a Program Performance report to show the overall number of people it was sent to vs the total number that navigated to fill out the form. And since you can only have 1 status, it will avoid some the data discrepancy others are seeing in this thread with the Landing Page Performance report.
I realize this doesn't address this thread's reporting issue but it's an great reporting method many enterprise customers use.