I finally found out about the secret basement full of bobbles at Fenway Park. Recently, I had the opportunity to take a private tour and I asked if we could take a look at the lower level. Access was granted.
Well here it is. The arrow pointing to the stack of bobbleheads is in the basement where they have about 15 workers. At night time, you can walk on Jersey Street and look down and you'll see about 30 bobbles thru a faded glass window.
This was the best picture I could take as it was highly guarded.