Furthermore, if Draco was seriously harmed there is absolutely no way Hermione wouldn't have seen him to Madam Pomfrey. Perhaps it's going to be made to look like Hermione did something unfair, like tried to cast the Killing Curse?

As for the monitoring, it's possible Lucius didn't need to write but also didn't want his son to know how much he knew about what goes on in Hogwarts.

And as to his goal, I suspect getting the twelve-year-old's wand snapped is not his end-game. However, he could definitely get some leverage over Dumbledore if he has a serious case.