Hi @Daniel Hult,
Welcome to the forum and thanks for joining Club GreenSock. ScrollMagic isn't a GreenSock product, but I'll answer this for you.
You're pinning the .trigger2 div which is a child of the middle section. If you want the next section to wait for the pin, you need to pin the parent section of trigger2.
ScrollMagic also has a support area here:
And premium support here:
Happy tweening and welcome aboard.