The real question in this discovery is, does "The alchemist’s bombs now have a splash radius of 10 feet rather than 5 feet." mean "All the Alchemist's bombs with 5 feet splash radius now have a splash radius of 10 feet rather than 5 feet." or does it mean "The alchemist's explosive bombs now have a splash radius of 10 feet rather than 5 feet." ?
If it is only the explosive bomb, why doesn't it say like in other bomb discoveries: "When the alchemist creates a bomb, he can choose to have it 10 feet radius rather then 5 feet and Creatures that take a direct hit from an explosive bomb catch fire, taking 1d6 points of fire damage each round until the fire is extinguished. Extinguishing the flames is a full round action that requires a Reflex save. Rolling on the ground provides the target with a +2 to the save. Dousing the target with at least 2 gallons of water automatically extinguishes the flames."