While you really need to be a Pollyanna to believe that Roy Williams did not know about all of this fraud, the 2005 title team was populated by AMFAM majors who were not taking real classes and, instead, were taking classes to remain eligible (that did not require class attendance and were graded by someone other than the assigned professor).
Rashad McCants, a starter on the title team, has stated that he never wrote his own papers and went over and picked up the papers he had to hand in right before he had to hand them in.
I do not see how the 2005 title is not vacated. Then you have the 2009 title, which occurred right as UNC was ending the program (the primary person responsible for the program was retiring). That one would probably also be vacated if the NCAA had any balls, but I imagine they will say that there is not enough evidence.