Underneath a picture of a cow, text describes the Zionist movement which used a “faked a mass killing of your own kind.”
It went on to say Zionists used the “faked event to guilt the major powers into giving your people an exclusive plot of land.”
NUJ General Secretary Michelle Stanistreet said: “This was not material known or made available to the panel considering the complaint.”
They added: “The content of that tweet is shocking and vile in tone and content.
"There are no circumstances where it would be acceptable for an NUJ member – or any sentient person – to generate or retweet such disgraceful material that seeks to deny the Holocaust.
“Such views must never be tolerated and to re-tweet such claims is to provide a platform for antisemitic material. As the NUJ’s General Secretary I could never defend such actions.”
Ms Wajid has been approached for comment.
An NUJ panel "unanimously found that Ms Wajid was in breach of her membership responsibilities" over the original tweet, the union said.
“The NUJ does not regard prejudicial language or comments about people on the grounds of gender, ethnic origin, sexual orientation, age or disability as acceptable behaviour among its members,” it added.
Ms Wajid was tweeting in response to Tony Greenstein, an anti-Zionist who was expelled from Labour last year.
She said: “Do you really believe the likes of Adam Langeleben, Ruth Smeeth and Louise Ellman have a conscience?
"Don’t know what runs through their veins, not human blood. Their hearts and brains totally devoid of humanity and eyes blind to truth. No creatures in Abraham’s universe.”
The tweet was later deleted.
The panel's findings raised “deep concerns” at a number of “breaches of procedure and unacceptable behaviour during the process.”
The JC understands that the NUJ members who made the original complaint were subject to pressure to drop the complaint by members who supported Ms Wajid.
The findings refer to one complainant whose confidentially was “breached” during the process.
“The panel is concerned that such breaches could deter members from using their rights under rule to take a complaint,” the findings said.
According to her LinkedIn, Ms Wajid started work as a newspaper journalist in 1980 and worked at the BBC World Service from 1990 until her retirement in 2010.
She also says she has continued to train journalists since her retirement.
Ms Wajid is a Labour member and is understood to be one of 50 cases about antisemitism that Tom Watson documented and sent to Jeremy Corbyn in February demanding that action be taken.
The dossier includes party members sending tweets linking Hitler and the Rothschilds, accusing Jews of murdering children and questioning whether Jewish MPs and councillors have “human blood.”
Mr Langleben said: “Thankfully good anti-racist journalists no longer have to share a union with this individual.
"Deciding to jump before she was pushed was probably the smart move on her part.
"It is unsurprising however that she remains a member of the Labour Party. I want to thank the people who unknown to me had put in the complaint to the NUJ on behalf of myself, Louise and Ruth.
“There have to be consequences for antisemites and this is a small but important one.”
Labour declined to comment.
