Is that the only thing you're basing it on?
That is more than sufficient evidence, based on Larian's history.
The evidence that it won't be released for the Stadia launch is also based on the common sense that you don't just drop a huge blockbuster game in two weeks from now completely without marketing. Since the game won't be ready for Stadia no matter what, that makes them immune from pressure to have something for Stadia's release.
