It's pretty simple. After the release of Divinity II Ego Draconis, Larian released an extension called 'Flames of Vengeance', which (1) fixes major bugs and patches graphics and more (2) provides an extension to the campaign (fov). For those who didn't have DivII yet, the 2 were packed in one bundle : The Dragon Knight Saga. Recently some other extensions were included into this, resulting in Developer's cut.
Now that you got the Dev's cut you can (1) start from ED with level 1 hero (2) skip the first part and start immediately with Flames of Vengeance.
In short, the answer to your question is YES.
I assume you got it with the 80% bundle?
Enjoy your game!
