For my Lestat and Louis muses, yes, they do know the VC books/movies exist. I think most VC RP muses know the VC books/movies exist, including the other adaptions. There were official graphic novels of the 90′s, Claudia’s Story (the graphic novel of IWTV from Claudia’s POV), and the Lestat musical.
If you say you’ve only finished one book, you’d have to specify which book.
They tend to tease eachother about the casting choices or acting of their characters in the films.
Armand about Lestat: “Tom captured your obnoxious attitude perfectly. I almost forgot it wasn’t actually you on screen.”
Lestat about Armand: *huffs* “At least I was played by someone who resembles me.”
[X] In canon, the vampires haven’t mentioned any of the movies or graphic novel adaptations, but the books themselves are acknowledged as existing. Some in-universe characters take them as bibles, others laugh at them as cheesy or awful fiction.