He was patched on an update to make him rarely spawn, if you delete your updates ( clear the system cache) and play offline he should spawn quite frequently in sanctuary. --- Xbox live gamertag - SavageTBK
If you have a mission called doctors orders for wildlife preserve still available you can use that to farm for them. In an area by a certain holding cell there is an area with one of the quest items. The 4 boxes have extremely high chances of spawning a loot midget. Use that to find jj but don't pick up the quest item until you found him as many times you think is necessary. --- They're not going to say no because of the implication.