Makes no sense that Rudy would take the phones to prevent Meredith from calling for help. Had be been the lone wolf then he clearly knew she was dead when he left because she was covered with a duvet.
He did not take them to sell for money clearly because they were thrown away.
The plausible reason anyone had to take the phones IMO was to prevent them being heard ringing behind the door, so as not to pre maturely discover the scene. Otherwise the "I called Meredith" excuse doesn't work. Had they been ringing behind the door and no answer from Meredith, there would be no excuse to not call the police immediately.
Yes.
ETA: There was a theory that Guede stole the phones to sell them for cash, but became frightened when they started ringing, and flung them into the ravine.
re Knox and Sollecito: The only question is, why not turn them off, so that they could say it went right to voicemail? (and no ringing would be heard). anyone cover this?