Current thought is that it is the core of a galaxy ripped apart by the Milky Way, not a Globular at all.
I have never heard of there being a black hole in the middle, but, there has to be something rather heavy in there to keep all those stars from flying away and keeping it’s rather round shape (actually it’s rather flattened, but...).
Then there is this article from 2008.
http://www.spacetelescope.org/news/heic0809/
Apparently Hubble found one.
Wow! Thanks for that link!
I never cease to be amazed at what is out there.