A report on Queensland's flawed trains is yet to be released, but top bosses have been kept in the dark about design flaws, including toilets and aisles that breached discrimination laws.
Retired judge Michael Forde said middle managers did raise other issues with the trains but not the ones that have left disability advocates fuming.
Queensland has copped a bill of at least $150 million to fix problems with the trains, worth $4.4 billion.