Perhaps the film opens with Dryden arriving at the high-tech modern office building in Prague and the shots of the dark figure walking along the street and the guy going up in the lift are Dryden and not Bond. What if Bond were already at Dryden's flat, sitting, waiting in the dark for his target. The flashbacks about the first(messy) kill in pakistan could be intercut with Bond's confrontation with Dryden which is more pyschological than physical. What if the shot of what looks like Bond in the lift with the doors opening is infact played in reverse in the trailer. Look at the button, down is lit up. Perhaps this the final shot in Dryden's place as Bond is leaving or it may be from another sequence in the film or Maybe it's not even Bond in that lift but Dryden again. Just some thoughts on the matter.
That sounds similar to my suggestion on the matter, although you know a little more than I do
I have to say your sugestion is pretty much a decent description of what may happen.