Steve Eling believes he was part of a "political witch hunt" stemming from the very top of the party.
He was suspended in January 2019 following an undisclosed complaint and has remained under investigation since then.
Mr Eling claims the party's former general secretary, Jennie Formby, tried to influence the result.
Councillor Yvonne Davies, who was suspended by Labour in July over a number of tweets, was eventually elected Sandwell Council leader.
Wednesbury North Councillor Luke Giles claims he was bullied and threatened with suspension if he did not vote for Councillor Davies.
Councillor Giles says the threat was made by the current councillor leader, Maria Crompton, under direction from Ms Formby.
Ms Formby resigned in May 2020 following the election of Sir Keir Starmer as the party's national leader.
With a new general secretary in place, David Evans, Mr Eling has penned a new complaint to party bosses.
Mr Eling told the Express & Star: "It's all started to come out about all the bullying of people and the involvement of the former general secretary, Jennie Formby.
"That's why they wanted to get me out of the way. I have written to the new general secretary saying I have been subjected to a gross injustice.
"It is a new general secretary. I'm hoping the wrongs of the past are going to be put right."
Mr Eling referenced de-selections of councillors ahead of May 2019's local elections, including Joy Edis and Carol Goult.
Asked to clarify his claim that Labour wanted him out, he said: "That's when they did the dodgy de-selections of long-standing councillors.
"The party knew I wouldn't put up with that without a challenge. I always thought getting rid of me was purely political and involved the likes of Jennie Formby at headquarters.
"When Yvonne Davies became leader, after yet more Labour members had been suspended, which impacted the result of the vote, she publicly thanked Jennie Formby in the annual council meeting for her help.
"It all adds up that this has been a political witch hunt that has attacked a number of people including me."