>>274493994
Okay, cool. I've solved it, sort of. 

Apparently when you get this mission I have, and reach the island, you're meant to unlock a new upgrade which causes your hand-laser to create updrafts in the cloud, causing you to launch into the sky when you boost into them. 

I haven't got the upgrade available, nor did coming to the island trigger message about it, like i'm seeing in videos. It's meant to be in the "Attachments" section of the weapon table and cost 1500 alloy, but it just isn't there for me. So I guess i'm boned because it is required to progress.