I've never heard of any recalls on bicycles for defectively manufactured equipment, and I if you were able to sue the bike manufacturer on this merit, you'd probably be the first setting a Precedent case.
Furthurmore, Walmart, as well as most, if not all bicycle dealers, have store employees assemble their bikes, which come in boxes, of which could have been the cause of such failure, especially if they rough-assembled the bike, not tightening all the bolts securely, to allow them to quickly put the bike on display.
For this reason the "pack your own parachute", or "if you want the job done right, you have to do it yourself" applies, and you should pre-operatively inspect your bike for loose bolts/nuts before and after any off-road mountain biking, as bolts/nuts can loosen with vibration, and thus the failure could be entirely due to such vibration/loosening.
Also if you squeezed too hard on the brakes, it's possibe you could have snapped a brake cable, although this is less likely.
Lastly bikes have 2 brakes, so if one fails, you should be able to stop safely with the other, although this is less true for steep off-road downhill descents.