first of all, if u are trying to do the vault run, keep in mind u need 1 of 4 dragon keys in order to open the vault after u actually found it, and the key that is required would be random each time u go in and by equipping them u'll also suffer a penalty such as reduced speed, attack, HP or shield. it is strongly recommend that u run this with a full team and each bring a different key in order to have 100% chance to open the vault once u found it. as for tough "leaders", u sure that Napalm does have the blue color ice shield thing on which would block all projectile weapon? what were u using?
u can have multiple bp of the same one in ur inventory, it won't take up extra space. u only see 1 in the foundry is because (I'm guessing here) u had made one already, it would show how many of the finished product u already have along with the mats u need. u can keep all the extra bp if u want or u can sell them too, all up to u.