Many people reporting the problem so it is not a cat unless it is very well travelled and has a grudge against Dell laptops.
It could be that every owner has a cat and they all feel the need to mark dell laptops as their property but that seems unlikely.
If you read the comments you will see that they did not all immediately reek but it happened over a few days which rules out a batch getting watered en route since they would stink when removed from box (and probably suffer other problems, Laptops + liquid do not mix)
That is even assuming said liquid could even make it to the laptop through all the packaging.
It sounds far more like a reaction to hands + chemicals in/on keyboard or maybe chemicals used to create keyboard gradually reacting to heat of laptop.
Especially since people have provided links in threads detailing how this can happen.
So occam's razor, something in the manufacturing process; even if it is just one batch.
