"I think you're referring to a negotiation that happened with Kieran Foran back in 2011 or 2012," Greenberg said.
"I'm completely aware of that. I'm completely comfortable with my track record, both in the club and with that particular negotiation. He ended up not signing.
"I've been a proponent of players earning additional income outside of their contract fees but understanding about the rules. So I'm very comfortable."
Asked if he was worried he had become a target of those he was investigating, Greenberg said: "I've been around long enough to know sometimes these sorts of things happen.
"It happened around the Parramatta investigation. I have to make the best decisions for the game, I have to report to a chairman and a commission and I have to be completely transparent with them.
"Leadership and popularity are different. I'm going to have to lead on this decision and we will. It won't please everyone and I understand that."
Greenberg said he had not done anything illegal in his attempt to lure Foran to the Dogs along with then coach Des Hasler.
"The irony is when I took this job, one of the things people said was 'it's great to have someone that's experienced at club level'. But when you've been at club level, you've been experienced in all these things," Greenberg said.
"Everyone comes from somewhere, I enjoyed my time as a club CEO and I'm very comfortable with how I handled myself."