Your people can probably complete a project audit, but does it give you a business view of how the project is progressing? And does it suggests actions that should be taken?
Do you have this feeling that everyone says the project is ok, but you are still worried?
There is a difference between a technical ok, even a project management ok, and a business ok.
Projects that go wrong are an expensive drain on all business resources, and they often go wrong at a level that is outside of the technical control of the project. They go wrong because of the human and cultural factors, or because of relationship issues, or a number of other organisational factors outside of the project but impacting on it.
Project Business Reviews are a tool for project owners, not project managers. Whilst they will report on technical strategies and project management issues they are primarily directed at issues that could cause a business failure.
Talk to Stratege about a project business review for your critical project, you will be surprised how quickly they can be completed and the insight they bring.