Hang on a minute. If the crew were able to talk with MedLink and they advised that there was no emergency and it was considered that they should carry on to destination which was at least another 6 or 7 hours away then there was no 'EMERGENCY'. If there was a deterioration in the patients condition as they approached LGW then that is a different matter.
Why wouldn't the crew wait another 10-20 minutes in the hold? It's not as though they couldn't have called Ops on the Sat Phone any time in the previous 6 or 7 hours to advise them that they would need an ambulance to meet the aircraft but there was no 'EMERGENCY'. Even a simple call to Ops on the VHF whilst approaching london and they could have had the ambulance ordered and waiting for them by the time they arrived on stand.
Nope, this one does sound as though an emergency was declared when there wasn't one in order to get an expeditious arrival. Just because btsm doesn't believe it doesn't matter. Unless the patient was indeed in serious danger of deteriorating with a life threatening condition, declaring an emergency just to make sure an ambulance would be waiting when they have had many hours to make a call to their ops using Sat Phone, HF or VHF (within range) is an abuse of the system.