I saw the video, and that is most definitely a solid fuel missile going up. They do not show the origin of the launch but for an instant, but you can see the cloud of exhaust at the sea surface.
Google up a few images of sub launched missile shots. It will be very clear.
Looks like pretty soon after launch.
I think it’s most likely an airliner. It’s just too slow to be a missile, imo.
As far as the origins of the trail and the angles, I think those can easily be confusing and misleading.
I’m happy to investigate further though if we get any more info or any better imaging.