Would you like to know why?
Because
Low Template DNA analysis has not been accepted in US courts, and requires special laboratory procedures to be used. Also, a biological substance must be identified, generally a bodily fluid, something that establishes the probative value of the sample. Like blood under fingernails, saliva in a bite wound, semen in underwear. They don't just sample
everything and try to tease a profile out by using suspect-centered methodology (having a reference profile and then looking for it in the samples) from an unidentified substance which may have nothing to do with the crime and was transferred innocently--or the result of contamination.
Many of the Rudy Guede samples were low template as well and were found all over the crime scene, whereas nothing from Raffaele or Amanda was found during the initial forensic investigation. That means everything was tested to the lowest level and only Rudy Guede showed up, nothing from Raffaele or Amanda even using the least reliable methods. In Guede's case having never been to the crime scene and having admitted to being there when the murder took place there's no reason to doubt the legitimacy of the DNA found. That doesn't hold for Raffaele who was at the discovery and was a visitor to that cottage the previous week and with the condition of the scene resembling
Mount Trashmore anything could have transferred, there's no way to establish any solid probative value for DNA found.
You cannot compare evidence from the two different methodologies, however you can note that all that DNA was found from Rudy Guede but nothing from Amanda and only the bra clasp from after the scene had been reduced to a pile of rubble by the
polizia scientifica.