RCMP continue to investigate Thursday’s crash on the Trans-Canada Highway between a semi-trailer truck and a minibus taking seniors on a day trip to a casino at Carberry, west of Winnipeg.
Ten people remain in hospital and one of the six in critical condition has been upgraded.
Mounties say they have yet to speak to the bus driver as he is still receiving care in hospital.
Police have said dashcam footage shows the bus was crossing the Trans-Canada when it went the path of the truck.
But they say mechanical inspections and other checks are needed before investigators can determine exactly what happened.
Weather conditions were clear at the time. There was also a stop sign at the intersection with a yield sign in the median between the opposite lanes.
Stefanson says the province will make the appropriate checks but for now are letting the police investigation unfold.
“We don’t want to rush through this,” Stefanson told a news conference in Winnipeg on Monday.
“There are still investigations going on right now. We'll respect that process. But you know, an internal review is always taken.
“Because of the severity (of the crash), I think it’s important that we are willing to go beyond that, bring in experts where needed to ensure safety of people travelling on our roadways is the most important issue.”
