This dub was not in very high favor with Latin American audiences, mainly because of the fact that a lot of the profanity was censored and replaced with Mexican slang terms. The poor ratings and reception lead to the dubbing being discontinued.
Around the same time, another Latin American Spanish dub (produced in Miami, Florida) had began airing on Locomotion, dubbed by BVI Communications for season 1 and part of season 2, and Globecast Hero Productions for the remainder of its season 2. It found greater success due to the fact that it was less softened in the profanity department. This dub would shift through various ADR studios afterwards, and channel-hopped from Locomotion to MTV Latinoamerica in its eighth season.
Reason For Dub Loss
This dub is likely completely lost as not many people liked it, which would mean that less people would have recorded it onto personal tapes, leading to it fading into obscurity.
Another reason is because of the aforementioned BVI dub's popularity, between its initial dub of seasons 1-2 and the more recent 2011 redub done to keep voice cast consistency. On the Televisa DVD releases, the 2011 dub by BVI is used for the first two seasons, except in at least two exceptions; "Mr. Hankey the Christmas Poo" used the original 1998 dub by BVI due to strong criticisms of the redub's lyrical adaptations.
In the second case with "Chickenpox", a more peculiar situation occurred, and is noted below.
Bigger, Longer & Uncut
Both Mexican Spanish dubs of the movie South Park: Bigger, Longer & Uncut are not considered lost, because the film's rights are divided between Warner Bros. in Latin America and Paramount in the United States.
Warner's dub was produced around 1999 with most of the series cast, with censored dialogue and subtitled songs. This dub has frequently been broadcast on cable television, sometimes (ironically enough) on the Paramount Channel. Paramount's dub was produced in 2007, with uncensored dialogue and dubbed songs. This dub is available on the American Blu-Ray.
Season 1 in its entirety has been lost, and may have possibly been wiped by the network. However, some small parts of Season 2 have been easier to find, as MTV Latinoamerica aired this version once later on in its broadcasting of the show (due to Locomotion not being able to locate the BVI/Globecast version to pass on to the network).
One full episode has been unearthed, due to Televisa's Season 2 DVD release opting to use the Audiomaster vocal track for "Chickenpox" for unknown reasons.
The Mexican dub of the episode "Merry Christmas Charlie Manson" is available on Televisa's Navidad en South Park compilation DVD.
The theme song for season 2 can also be found, however, the original season 1 version is still missing. There is a slight difference between both openings, as Carlos Inigo's vocals for Stan were redubbed with Eduardo Garza's after the role had been recast.
Fragments of found season 2 episodes include "Gnomes", "Cartman's Mom is Still a Dirty Slut", "Clubhouses", and "Chef's Chocolate Salty Balls", all available on video-sharing sites.