The bad news here is that the Supreme Court of Appeal recently, in ruling against an unsuccessful tenderer (which had sued the South African Post Office for R514m for loss of profits), held that such a damages claim can succeed “only if it is established that the award of the contract to the rival was brought about by dishonest or fraudulent conduct on the part of one or more of the officials for whose conduct SAPO is vicariously liable, but for which the contract would have been awarded to the complainant.”
In other words, it is not enough to show that there were irregularities, nor incompetence, nor negligence – not even that you were more worthy of being awarded the contract than your rival. You have to prove (and the onus is on you here) that there was actual dishonesty or fraud, leading to your loss.