The tracks you are talking about are not remixes of Prodigy tracks. These tracks just sample some of Prodigy's music, that is all. I have a lot of such tracks on white, also the one you are talking about.
The track you are talking about also features samples from for instance Chemical Brothers - Hey Boy, Hey Girl. Who made this track is unknown in a way. First of all it has been released illegally as you might be able to imagine, so it's hard to say who's behind it in the end. Normally such whites have some references on it which state the artist or at least a nickname ;p
In case of this one it's being promoted under two different names. First of all there's Keith Mac & JB - Cocaine, but there is also a white which is being promoted as Dino Lenny - Voodoo Cocaine. Two names for one and the same white; one and the same track ;)
The other track you are talking about is by The Klubahoux and is indeed called Slap My Bass Up.
If you would like to know more information about these items and more, then take a look at a list of my own Prodigy collection available at http://www.the-prodigy.org
. On this list you can find catalogue numbers as well for instance.