"...with an alternative different party about..."
Redundant adjective is redundant.
"I imagine they had no choice because the cost of this exercise appears to be well above even their high-end cost estimates," Mr Turnbull told ABC Radio.
That explanation was more likely than bidders trying to rip off the NBN Co, he said.
Logic fail for Turnbull here - the two 'reasons' aren't necessarily mutually exclusive.