I never said I believe that's what happened, though I do believe there is a good chance. What I have always said was that the SP were completely incompetent, and that the way they handled and collected the clasp left it wide open to contamination. The whole point of ENFSI standards is to minimize as much as possible the risk of contamination. Once you screw things up like the SP did, the risk of contamination can not be ignored. You don't get to ignore the mistakes because 'you' can't visualize where possible contamination might have come from.
Can you offer PROOF she didn't touch Raffaele's DNA on the door jam before collecting the clasp? I mean, let's not forget, incompetent Stefanoni didn't even bother to test the exterior side of Meredith's bedroom door because 'the crime scene was on the other side'. So you can't even say if Raffaele's DNA was on the jam because it was never tested.
And lets also not forget that Raffaele's DNA was not found anywhere else in the room, nowhere on the bra or clasp except for the metal hook, the one place we know Stefanoni rubbed with her dirty gloves. Talk about a coincidence! So how did he manage to get his DNA on the hook, which isn't even exposed when a bra is worn, without getting it on the fabric or elsewhere? I've asked that question hundreds of times and I've yet to see a pro-guilt attempt to answer that.