Yes, the Stillwater Giant exists. The crazy scientist was right, he IS a blue bunny. After you did all the stuff with the blue bunny you probably bumped into the real one, after attackin the blue bunny it turned into the giant, whose skin you probably took. Unfortunately, if you go to the Tarantian Zoological Society, they laugh at you. You CAN, however, sell it to that dude who sells the fake Pelt (H.T. Parnell's, I believe), who will buy the real one from you for, I can't remember somewhere around 200 gold or something. Sadly, there ends the potenially cool path of the Stillwater Giant =(.
"Unlimited technology from all over the universe, and we cruise around in a Ford POS."
- Agent J, Men in Black
Do you feel the Call?