My guess is the dress shops. Was it Neobie who said this was diabolical because the streets were not on maps, and VERY difficult to find??
That combined with some Ferns giving out deliberate misinformation would explain a lot. (Which makes me SICK. If you can't help, at least don't hinder!!)
They were only an hour ahead, and considering all the teams from the second flight took METRO (the faster option), whereas only Jet and Cord took the metro from the first flight, that has got to be the first step to downfall for the twins.
Followed by the bridal shops which were NOT listed on the maps (some of them, till today) -> especially those hidden in the back alley (the one which Twinnies and Leo and Jamal missed!)
Considering Jet and Cord went into ONE wrong cubicle (20 mins) before getting into the right one and were nearly done (maybe 15 mins) before many of the other teams arrived and started on the task... the Cowboys should be about 35 - 45 mins before the other teams? Don't forget that the other teams were probably faster (shedding about 15 mins) because those ferns who helped the cowboys already knows where the shops are and bring the teams directly there.
So yea.. I guess the main reasons why the teams from the second flight could catch up and complete the bridal shop task so quickly was because of so many factors listed above. Plus those annoying fans who misled the twinnies and leo and jamal (?) to different wrong locations.