NSW Opposition Leader Chris Minns said Transport Minister David Elliott has still not given full details as to what he knew, and when he knew it, prior to the rail network shutdown on Monday.
"What's the point of having a government if the minister responsible is not even told, or does not know, what's happening on his watch?" Mr Minns asked on Wednesday.
Labor's transport spokeswoman Jo Haylen said it was "absolutely implausible that a public servant alone would shut down Sydney's transport network" without the minister signing off on the action.
"There are giant holes in the transport minister's story," Ms Haylen said.
A dossier from Premier Dominic Perrottet's office confirmed the transport minister had known about the shutdown from 10.43pm on Sunday night, she said.
"Either the transport minister is incompetent of running his own department, or he has misled the public and the parliament about his involvement," Ms Haylen said.
On Tuesday the government withdrew its claim against the Rail, Tram and Bus Union in the Fair Work Commission, after the union asked to see the justification for shutting down the rail network.
Trains resumed at limited capacity on the same day, and will continue at the same service through to the end of the week.
Most rail lines are reduced to running every 30 minutes, servicing all stops.
"As a minimum, the rail timetable being operated today will continue for the remainder of this week to ensure a basic level of frequency for customers who rely on our services while protected industrial action continues," Transport for NSW said.
In a bid to keep peace talks moving, the government is due to meet the union later this week to discuss a new enterprise agreement.
Mr Elliott said the government withdrew its FWC claim "in the interest of transparency and goodwill".
RTBU Secretary Alex Claassens said the withdrawal vindicated the union's industrial position and reiterated the rail network shutdown was ordered by NSW transport officials.
Mr Claassens said the challenge now was to get the system "back up and running properly", and pointed to Monday for a possible resumption of regular services.
"We're fairly confident we can do that, even with our protected action in place," he said.
