Hope it carbed for you. If not, hopefully others will chime in with some suggestions that are better than mine: You could try the carbonation tablets such as Prime Dose in one of the bottles If there are any yeast still alive it might give them a little pickmeup to carb the beer. If it works you could uncap, dose, and recap the rest of the bottles.
If the yeast are totally gone not sure what to do. Not sure what pouring 50 bottles into a keg would do to the beer, but you could at least force carb it that way.