First, there has been indeed one Sollecito's consultant who hinted at contamination from Knox's DNA on the clasp.
Second, but more important, the Y profile chart was available to Sollecito's defence since before the beginning of October 2008, if we believe Bongiorno when she said, on Oct. 4., that the defence had finally managed to obtain the charts the requested.
There was a defence report submitted on Oct.24. about that.
But then there was a subsequent request, from Prof. Pascali to the judge, by which he requested to have also the electronic data files, that he called "log files". Stefanoni answered to the judge saying she was ready to make the electronic data files available to the defence just like she did with the image files, but she put the condition that basically can only be interpreted as follows: that the defence would analyse those data files through the same computer, software and settings ("parameters") that the Scientific Police used, which implies: analyze them in her laboratory or under their supervision.
So Stefanoni said yes to this request too, she only put a condition on this.
After that, the judge decided the data were not indispensable to his decision, and the defence did not go forward with their request (they didn't go to the lab).