Lu Fan was not surprised by their offer. He had become someone with a lot of value they could not easily touch.
It was not that they were incapable, they were but they did not know that, it was just that the position they were in was rather awkward.
That is why the Han family was trying so hard to get as many favors as they could from Lu Fan. As for causing him harm, don't think about it.
Now they had to make sure that nothing even remotely bad happened to him. And if it did, it should have nothing to do with them.
If they could prevent it, they had to do so since they did not know how much Lu Fan knew and had prepared for.
Lu Fan could laugh if he knew what they were thinking.
It was not that he was above such methods, it's just that they were not worthy of such measures.