Sorry I'm on a different timezone so didn't get this until now.
Did you get it sorted?
The reason for the looping effect of the video is because of the "autoplay" setting i believe. Perhaps a mixing of the video syncing solution and the code you are already using would be a more appropriate solution.
So, waiting for the video to load. Once it's loaded play once and trigger start of timeline. Once the whole timeline is played (or when it reaches a certain point) reset loop counter so video will play once more when you have returned to the beginning.
Sorry can't be of more help.