Failed timber mill Tachikawa owes about $13 million, according to the initial receivers' report.
Just before Christmas, KordaMentha released the receivers' first report on the state of the mill's finances.
Tachikawa stopped operations in mid-October, with 130 staff being told they no longer had jobs.
According to the initial report, BNZ is owed $6.3 million.
"The company [Tachikawa] had incurred significant losses over the last two years, leaving it under-capitalised. We understand the directors were seeking to raise capital but were unsuccessful, and as a consequence requested BNZ to appoint receivers," joint receiver Brendon Gibson said in the report.