Missing Information
The article is not very clear and as a reporter she should provide more information. I will ask one question which has pouzzled me all along with this incident: If the Crew had a 24 hour lay over, why did the captain only have 3 hours of sleep? This is something which is worth addressing and investigating.
If the reason for lack of sleep is associated to Bad accomodation/hotel, sickness, ..... which would allow the Captain to refuse flying the return leg and that would be something EK would be responsible for it;
On the other hand if the lack of sleep is associated to party/drinking/shopping..... then this is not EK's responsability and the Captain should have known better.....