What became of the Serbs in the House of Money?

When I watched the Netflix series House of Money again, I noticed that at the end of season 2 the 4 Serbs simply disappeared. They help bank robbers out of the banknote printing works and after that I never saw them again. Does somebody has any idea? Maybe they'll be important again in season 4. Or have they just disappeared?

I don't care, it's just a TV series anyway.

They do what they did before.

They got their share and disappeared. The police never found out that they helped, so they are not searched.