LOL...I got a serpent star....I saw it when I first put it in the tank....it has NEVER come out since...for months I thought it died....but I found it in a cave...apparently it likes it there, and is happy...if I look at night with a light, I can see a leg swinging around, so I know it is still alive...It must get enough food back there too...
I wouldn't worry about the goby yet.....