That is correct but is not new information. Identifiable DNA from her older sister's boyfriend was found on Jodi's clothing. As already pointed out, the T-shirt had been borrowed from her older sister. Luke's DNA was never recovered from Jodi or her clothing even though it should have been present given that the couple had met earlier that day.
So I have to accept that? It is just your opinion that his DNA should have been present because the couple had been together earlier that day. You do not know for certain whether Jody bathed or changed prior to intending to meet Luke later . We also do not know for certain whether the DNA was on the t-shirt prior to Jody being loaned it, the prosecution speculated that it was and the jury must have accepted that. But, there are plenty of examples in which juries have gotten it wrong, the examples being in the many overturned cases which are available online, in books, articles etc.
<EDIT> The examples of overturned cases prove that the prosecution, and even forensic scientists, get it wrong also.