That is so not Kee. Kee didn't exist at the time of Air America, and in the beginning, Kee didn't make their regs, PSI did. Now, I am sure that they are made in China, but pretty much based upon the PSI, now known as Ninja, design.
To Schmitti, can you compare the fill nipple to another one? It may just need a new o-ring, but if it needs a whole new fill nipple, my first thought would be to compare it to existing ones.