Considering the effects of average current or winds alone won't explain the dispersal of the floating wreckage. The pieces will move at different rates and directions depending on their size and shape - what sort of "sail" and "keel" is presented to the wind, waves and current will determine what will move in which direction. Each piece floating aircraft wreckage piece is uniquely asymmetric as compared to "Floaties" and likely less predictable in current or original location.
Nature gives an example in
Vellela vellela - the By-the-Wind Sailor jellyfish. The are hatched far out to sea, half with "left-handed" sails and half with "right-handed" sails. In the Pacific, those with right-handed sails wash ashore in California, those with left-handed sails in Asia.