Warrants are sworn out on reliable information. Someone turning themselves in for one crime in order to report a more serious one is pretty reliable, especially when they bring tangible evidence of the greater crime.
This is NOT evidence which the State has seized illegally. It has been dropped into their laps by private individuals.
The only way this guy gets off is if there is nothing incriminating in the materials seized at his home pursuant to the warrant. If the only evidence is what the two burglars brought in, he does have a case that no one can establish these materials were in his possession.
And a good defense attorney will question their motives. Is there proof that the CD’s came from his home?