Well, on a website (I think it was Malasiana Tropicals), I read that N. faizaliana is from the Sarawak mountains or some place called Sarawak. This is prolly also where N. fusca 'Sarawak' is from. So, since they're from the same place, and look a bit alike, I suppose someone who can't tell the difference collected plants from the Sarawak place and assumed that they were N. faizaliana.
Here, I got this from BobZ's photo finder: Ch'ien Lee writes “N. fusca can immediately be distinguished from this species [N. faizaliana] by a triangular lid which can be very narrow particularly in the upper pitchers and frequently has a short apical appendage as well. The lid of N. faizaliana by contrast is nearly orbicular (sometimes wider than long) and is in fact much more similar to N. stenophylla". Further, Tony Paroubek writes:"N. faizaliana floating around that do NOT match the description of the species are very typical for N. fusca from Sarawak which is a very common plant there. Seed was distributed from ABG if I recall and several nurseries grew them up as N. faizaliana and distributed them as such, to retail nurseries, before they got to a larger size. The plants grown by Malesiana from material collected by Ch'ien do not look anything like these other 'N. faizaliana'."
-Ben