Anakin's turn to the dark side was multifactorial.
He lost what could have been an adoptive father figure in Qui-Gon, who was the catalyst for Anakin's training in the first place, and Obi-Wan reluctantly took on the role. They eventually became like brothers, but Anakin always felt the Council was holding him back from his potential, which lead to him being unable to save his mother.
This fear of loss, combined with the perception that the Jedi don't trust him, was fueled for a decade by another father figure in Chancellor Palpatine, who after years of enabling Anakin's frustrations, appointed him to the council knowing full well the Jedi would still hold him back.
Then Palpatine sold Anakin a lie that only the dark side was the way to save Padme after he was seeing visions of her dying. Anakin couldn't afford to lose the other person close to him and followed the wrong path.
But this all most likely wouldn't have happened if Qui-Gon had not died, hence why the score in TPM is Dual of the Fates - it's the fate of Anakin.
So I hope that if there is a Qui-Gon cameo - it's during a Obi-Wan/Vader duel and it addresses both of them somehow. That alone would turn the series around for me.
