I am not sure I fully understand.
Did you just say that the band leader aided in the investigation in this bust?
No, he did not help in the investigation. While serving his prison sentence for a previous drug offense, he continued doing business and cooking amphetamine, in addition to importing cocaine and heroin.
Traslation from the second article:
Ales Zupancic (LEADER) had already appeared on the Black Chronicle when he was tried for drug trafficking. Zupancic acknowledged the allegations and contracted with the prosecution in May 2018. The court sentenced him to two years of the so-called weekend jail. He was also fined five thousand euros. In addition, the specialized prosecution brought an action against him under the law on confiscation of assets of illegal origin. That being said, he was sentenced to a weekend jail in May 2018, but apparently the drug deal continued to run, given that criminal investigators searched the international community they broke up on Tuesday for two years.