Mission 11 - Before the Storm: Halo 5 Guardians Guide
Now that the Fire team has the Constructor which is required to activate the Guardian in Sunaion and take control over it. This Mission is the Shortest mission similar to Mission 9 Alliance. Let's Checkout what is Arbiter's plan to take over the Sunaion.
As you Begin the Mission you need to head straight to Palmer and report her about the current progress, but first just look behind there is a D-pad behind, a ring shaped on the top so grab it and then move forward for the Objective.
As you report to Palmer, she will ask you to wait until Halsey has the Constructor sorted and then we can move Arbiter's people to Sunaion. Now go and have a word with Dr. Halsey where she will inform you how she is using the Constructor to upload the recordings from Meridian into it and be ready she will give you the signal.
Hint: you D-pad to locate all the Collectibles nearby.
The Cutscene will start and End of Mission 11: Before the Storm where you did nothing, but just kept moving from one position another informing the Alliance.