It could easily be bidders creating gossip to try talking the...

It could easily be bidders creating gossip to try talking the price down to pressure the seller, nothing new in that tactic, its not a credible price.
NZ has non-current assets of $311m in the last update (excluding goodwill of 323m), if it went for $250, thats a discount on asset value, and giving away the customers for free. Spark boss quoted last year as saying its so competitive for customers its cheaper to buy them, so the customer base should be a significant component of the price.

If it turns out the bidders expect fire sale prices then a possible solution would be to float it rather than sell it off market, that would allow Vocus to get some cash and keep some interest in shareholding to sell and a higher price later.

Bidders would still want the assets and have to buy off the market which would be more expensive, it would take time though, so bankers would have to be onboard with it.

Selling a stake in ASC might not be a bad thing.