A perfect crime ??? Heavy spoilers

Taking ques from the other thread about planted evidence by willy and stating further

They are forgetting that bullet was never planted it was The shell casing

So
Let's talk evidence

One bullet --- dead girls head after Hopkins pulled the plug

Shell casing in evidence ---- don't match to anything gun is still not recovered


Hopkins own gun ---- not fired at all

Robs own gun --- killed himself / used to shot the girl


Not a single evidence points to Hopkins

He was quite genius and rob and willy just gave him a clear pass with planted evidence

a perfect crime?? in my opinion

Think about it what are the loose points in terms of the crime

You can't convict him.and than there is a double jeopardy issue also.