The approved secular booklist can be found on chinuch.org. Just type book list as the keyword. There are 2 versions, one with comments on each book and one without.
No pritzus in tintin? How about Bianca Castifiore !! JK Really the problem with tintin is adult themes other than pritzus, and a lot of violence.
It’s tough when you have a kid who loves to read, even though that should be a positive attribute. It’s a good question to ask, what do you do when your child finishes reading the first batch of mysteries. A kid with an unsatiable appetite for reading is never satisfied–you always need to be finding more books that aren’t objectionable.
What about the Jewish novels? There are at least a dozen of them that are mysteries and can be found in Jewish bookstores; for example the suspense novels of Yair Weinstock.