Interesting that he publicly whines about LE planting evidence in Ely. Sounds to me like he is worried that they will find something. But what?
Obviously, if they find her body there, it would not be planted. But maybe there is something else he tossed down one of those mines that he is now concerned about. The weapon? Her clothing?
His bloody clothing?
It would be better to throw those things in a dumpster .... which I believe may have been Susan's fate. Everything else may have been just obfuscation.