Unpopular opinion. I think when Louis left Daniel with Armand in the end of season 2 he did wanted (perhaps subconsciously, but still wanted) Daniel to be k*lled by Armand. So:
A) Lestat would never had a chance to know how Louis has told their story.
B) Louis wouldn't have to get his hands dirty
B) He could deny before himself that he caused this death and pretend that he did everything he was able to do to protect Daniel and just blame Armand for his death. Because it was all Armand's fails and Louis was a good person who did his best!
Because there isn't any universe Louis could believe he would be able to really kill Armand. Or any universe Armand would belive that Louis has any chances to kill him.











