"Rebecca Wilson was one of the most fearless and most intelligent women who reported on sport. She deserves the highest respect," Lumby told the Daily Telegraph.
"That she was abused and harassed in this manner by a football player is disgraceful. I am appalled that harsher sanctions have not been applied given that there is evidence of this behaviour.
"If the NRL wants to genuinely show leadership, which it has, in relation to the treatment of women and respect to people generally, than it needs to walk the walk, not just talk the talk."
Wilson's husband, former News Corp Australia chief executive and chairman John Hartigan revealed Foran had allegedly abused Wilson through text messages and a phone call in the days leading up to her death.
Hartigan told Fairfax Media: "That abuse caused greater hurt and pain to my wife in the last days of her life.
"It appears the NRL has given him the green light despite his behaviour.
"If they really have standards, for the sake of having a supposed star in the mix, they've dropped the flag."
Wilson lost her battle with cancer in October.
Hartigan revealed police told his wife to press charges but she chose not to.
"He sent her a text first and it was just horrible," Hartigan told Fairfax Media. "She didn't get unsettled too often but this left her really distraught.
"Then he rang and started abusing her again, that's when I pulled the phone off her and I said, 'if you want to threaten someone, threaten me but don't threaten my wife'.
"She felt so distraught that she rang a contact at the police. We wanted him told that under no circumstances can he contact her with that disgusting nature of his threats.
"Bec didn't want to press charges, she just wanted him to be warned off."
Wilson was one of the first to know about Foran's breakup with partner Rebecca Pope and the impact it was having on his football career.
Asked if Foran's mental health issues should be taken into account in respect to his punishment, Lumby argued: "Yes. And I am concerned that anyone who is stating mental and personal issues, they must be dealt with off the field.
"They should be given support and the NRL provides excellent support to players who need that."