Another strong piece of evidence is the fact that Wakanda serves as a major set piece in Avengers: Infinity War.
The trailers show off a massive battle between the armies or Wakanda and Thanos, with no explicit reason given as to why the battle is happening.
It could be that Thanos is just trying to take the most powerful player out of the game, but considering that Thanos’ whole objective in this movie is to find the Infinity Stones, he could also be launching an assault to claim the Soul Stone from Wakanda.
It would certainly justify why so many of the Avengers are present as they make a grandstand to stop the final stone from reaching Thanos’ clutches.