Yes it might be.I just found an old article that mentions that...

Yes it might be.
I just found an old article that mentions that figure but also mentions some tax writ-off advantages that went along with the acquisition. There was also the need to spend substantial amounts annually on maintenance.
I presume that putting the fibre towards a new NBN company would be where the possible value figure is coming from.
Not sure.

http://www.smh.com.au/articles/2004/02/18/1077072712290.html?from=storyrhs
"The failed Nextgen had been acquired for an estimated $7 million in December, and he said he expected the 8400km fibre-optic network - which cost $850 million to build - would break even within the year.

"There was a lot of press speculation we acquired the asset for tax purposes but that's not the situation. We had to convince ourselves there was a business case."