"an SIA spokesman said the airline was not able to comment on individual cases." ... perhaps they have already had papers sent to them by a lawyer, so feel they cannot comment. Not sure how many airlines would divert given the costs for them (presumably they may need to have another air crew to take plane to final destination, may have compensation to pay to other passengers, and will have aircraft off schedule with consequent delays and chaos to cope with).
I'm not excusing the airline, but trying to consider how an emergency diversion, landing, and delays may affect them. I suppose the delay may be limited to an hour if an airport allows emergency landing, refuelling and gives the plane a take off slot as soon as it is ready to go, so the only delay is that of adding fuel while the patient is taken from the plane...