Well it could have fallen off the plane ... there are precedents for that.
Besides its a question of resources, that bomb is only used in two locations ... Megaton and Fort Constantine, its unmarked (unlike the crashed Delta IX rocket in Vernon Square) so it does not make much reason for then...
Sorry but there is only one process and it does not matter were they originated ... Super Mutants are created by being exposed to the FEV and they are sterile, eventually they will catch on about not having female Super Mutants and not having little Super Mutants being born at some point (unless...
Sorry but that makes no sense, the only reason they did it on Fallout was because it was part of the Master Plan ... the Master is dead, Super Mutants are a evolutionary dead end and they know it.
Taking "humans" as slaves ... yes, I get that because most Super Mutants are not really much on...
The issue is FEV started as the PVP, a immunity vaccine developed at West Tek.
Then it became the FEV, the Mariposa Military Base was build just for FEV research with West Tek being cut from it when the military realized PVP value for a "super soldier" program, West Tek did retain FEV vats...