To start off, let’s lay out what the secret ending entails. After the credits roll, we see illustrations of several key moments in the Dragon Age series. This includes Loghain betraying the Grey Wardens in Dragon Age: Origins,

The Veilguard players are familiar with their companion hub, the Lighthouse, but this was not the planned location from the start.

Inquisition's final DLC, Trespasser, stated that elves across Thedas were joining Solas' cause. However, as fans are now pointing out, they're nowhere to be seen in Dragon Age: The Veilguard. Concept art suggests they were going to be in The Veilguard,