The 25-year-old fell out with Hoffenheim in January after failing to attend a training camp, which he insists he was given permission to miss but something Tanner denies.
Ba had been set to join Premier League side Stoke City, but a problem during the medical examination ruined a potential transfer at the last minute and he then joined West Ham before the transfer window closed at the end of January.
The African says his reputation in Germany has been destroyed by Hoffenheim and revealed he had turned down a lucrative offer from Russian side Rubin Kazan.
"Mr Tanner has ruined my image in the Bundesliga," Ba told German magazine Sport Bild.
"I only heard these words: 'Demba is only after money'. The truth is that I could have earned much more money elsewhere.
"I was presented with an offer from Rubin Kazan. They wanted to pay a €15 million (£12.73m) fee. I could have earned much more there than at West Ham.
"It's not all about money for me."
But Ba's behaviour has won him few fans in Germany and Hoffenheim owner Dietmar Hopp said the player's attitude left them with no other option than to sell him.
"If there were a solidarity fund in the Bundesliga to punish players like him, we'd pay into it," Hopp told SID, a subsidiary of AFP.
"If we had left Ba sitting in the stands, we would have paid him a total of 4.5 million euros of basic salary up to the end of his contract.
"Now, if everything goes well, we will get five million euros of transfer money."
Tanner insists Demba never had permission to miss the training camp.
"Demba wants to put himself in a positive light, but that is just a flat lie," said Tanner.
"He was always told that he could not leave during the winter, we had told him that he had to work."
Having made no secret of his desire to move to England throughout January, Ba has been impressive at Upton Park, scoring three goals in three games.