where has it been said they are being asked to give false evidence (I agree that is highly illegal)?
From the bits that have been said in the media, it sounds like they have convinced 1-2 to spill, and have then used that to break down the others (i.e. "we already know about the meeting, we know this was said, and we know you were there. you can either continue denying it, and say bye bye to your AFL career when this is done, or you can help us out and tell us your version").
Having a cop doing this, I'd be confident he knows the rules of interrogation well. 100% agree though if anyone is forced/induced to say something false, the book should be thrown at those who did it (days of cops working you over with phone books and fitting people up are supposed to be over, and there is definitely no place for it in AFL - its only footy FFS)