Apologies, Rod is correct, it is incredibly unlikely specific performance would be ordered, I merely mentioned it given it is the only feasible outcome in the absence of damages; at least in my opinion.
I had a quick look at some past cases and found a similar case, although with some fundamentally different material facts -
Citigroup Global Markets Australia Holdings Pty Limited v David Walker 233 ALR 687 - where Citigroup was liable for the economic loss suffered by Mr Walker after rescinding an employment contract - NB: Mr Walker resigned from another employer join Citigroup, hence the significant damages - He also earned $1 million + p.a. so likely had more QC's than Queen Elizabeth. If you check out where that case is cited you might be able to find a more relevant example to your situation
Also, the fact you mentioned the medical situation is good, indeed it may be discrimination depending on the illness and whether they revoked the offer for this reason or another reason altogether.
Let me know if you have more questions