You'll have to decide whether it is worth it. I am not sure about Camera wksp or Prime, but I was quoted $60 by Canon to clean out a Canon lens.
If the fungus has been in the lens for a while, it will do two things :
1. Eat up the lens coating
2. Etch the glass itself.
If (2) has happened then you can use the lens to produce some funky effects. If it's not an expensive lens I'd suggest junking it. Even if you have it cleaned, the coating and glass may be permanently damaged in which case you'll never regain the image quality.