The new Vader line doesn’t make sense to me. How would it be a good thing to account for your failure to the Emperor?
Well, the idea is that Krennic in his hubris knows that “I will not fail”. He has always been wanting to go up the Imperial ladder and now he’ll get an audience with the Emperor himself. By the time he’s going to meet him he thinks he will have solved all of the issues regarding Galen and such. Little did he know that Galen had a daughter who was growing out of apathy.