From all the reports I read I thought it was more to do with the club suggesting that players will receive TPA's during contract talks.
If the club has suggested that either of the 2 examples you mention above TPA's were part of their package then they are in trouble.
Example.
Players A,B,C,D have a TPA from car company. Player E is new to the club and during negotiations the club suggests that he can probably receive a similar TPA to players A,B,C,D. If there is evidence of this, there's trouble.
I'm not saying that I agree with any of it at all but from my interpretation, that's what the trouble is.
For the NRL not to interview those people tells me it's nothing they've done. It's more the way the club has dealt with the TPA....which of course they are supposed to have nothing to do with.