Yes no doubt there was a stuff up but I wouldnt say its 100% engineers fault. They are contracted/paid to come up with a design that meets the budget of the project. Engineering Dept can show several designs at different costs and risks associated but at the end whoever approved and accepted the risk is at fault.
We dont know.. perhaps at the start of the project they believed the budget was enough to cover. Once you start doing the final design/costing, thats where it adds up and could have blown over budget. With investors promised a return & capital locked, cost would have been cut to squeeze within budget. Most likely the order was given to cut costs, changes were rushed, materials swapped, support beams deleted etc to deliver something which falls close to budget.
If the project manager was guaranteed that it wouldnt fail then I would agree that the Engineering/design team was negligent. If there was a risk, thats where management decide to ask for money or accept the risk...
In the end, its nothing new. Many large ferris wheels built around the world. We know it can be built & material composition, structure & loading isnt complex,
The buck stops with how much money they are willing to spend on building one and whoever thought they can build a ferris wheel for that amount of money in Australia.
Also well aware of IRR, NPV etc when it comes down to capital investment & approval.
Discussion was not tailored towards Chartered Accountants