If someone is on probation and they decide to inform law enforcement about undoented workers who work where?

they used to work themselves can they get into trouble and thus violate probation? lets say that they didnt get into trouble because their probation officer cleared them of any wrongdoing, can the company that got reported by that former employee take retaliatory action against that former employee? lets also say that in the distant future that former employee decided name that former employer in their resume and their new employer asked about getting in contact with them, can their former employer retaliate by saying what they did in letting immigration do an investigation that eventually led to a raid? what evidence/proof is gathered that leads to a raid being done where undoented workers are at? what are the repercussions in the long run for both parties? can a legal expert please answer this complex matter..........