Bedposts and hockey pucks. Its anybody's guess. The operative word being 'guess'.
We could make a more educated guess, though. The DNA strongly suggests an unknown male sexually assaulted JBR. Dont take my word for it, that is the current momentum that the case actually has (RDI has lost any momentum).
It follows from the sexual assault by unknown male that the injuries to JBR's head and neck and elsewhere, were the effects of a brutal murder. Its more likely JBR was struck with a blunt instrument that, like many other items, cannot be sourced to the house. This is not surprising in the IDI scenario, as many items can be brought in and taken out.
A good sign for RDI that this is the case is LE failure to locate the blunt instrument or surface that JBR hit her head on. LE failure to locate cord or tape remnants or rolls, pineapple containers, or handwriting match. These failures, AND the existence of unknown male DNA is all part and parcel of IDI.