As he lost the engine say 25% into his flight he would have landed at WSSS having eaten a small way into his diversion fuel. It is acceptable practice under Eu ops to throw away alt fuel if desination has more than 1 runway. (do not know about Singapore regs). I know the 747 from LAX divided the camp as to whether it was wise, I wonder how the camp would divide on this one?
That's just gibberish.
The additional burn (to continue) from roughly 2:45 into the flight would have been in the order of 15 tonnes. As it most probably would have been planned to arrive in Singapore with approximately this figure, then any decision to continue would have been poor in the extreme.
Safety heights on the Afghan route that he was most likely using also exceed 18000 feet. The loss of another engine, which any pilot must consider, would put you into the unfortunate situation of not having enough performance to remain above the mountains.
Alternates for the 380 are pretty thin on the ground. Whilst places like Ashgabat are available as emergency fields, between Singapore and Europe, only Hyderbad and Dubai are full alternates (for us). Dubai was a long way further away than Paris, on a totally different route. Returning to Paris seems pretty much a 'no brainer'.