hello, just wondering if you worked out how to fix this as I'm having the same problem?
I exported it from Fusion Studio as a pro res, there was no stitch line. I worked on it in AE to get rid of the tripod and there was no stitch line.
I imported the composition into Premiere and there is a stitch line. I'm about to export the project and I'll see if it remains once everything is rendered but I have a horrible feeling it will still be there so any fixes before I do hours worth of rendering would be gratefully received!