Alan Little and Glenn Roche died from extensive burns they suffered in the April 2012 explosion that also injured 22 others at Lakeland Mills in Prince George.
The inquest began in early March, sat for 18 days and heard from 47 witnesses before lawyer John Orr asked for an adjournment to analyze new material.
He said the BC Coroners Service was unaware of a separate probe performed by a Seattle-based forensic engineering firm, CASE Forensics, at the request of the mill's lawyers.
Orr said WorkSafeBC knew for at least two years about the investigation.
The coroners service says the lead investigator for CASE Forensics is expected to testify about the firm's own probe on May 11, and will be followed by other witnesses, including senior personnel from WorkSafeBC.