I was going to say that the price is pretty average for parasailing - it is an expensive experience (and way too short!). I did it years ago and highly recommend you try it once!!!
DH and DS (12) did it on CC in Nov, LOVED it! DS tandem'd with a little girl from our DIS group, and DH went solo.
Re: the release form, I don't know about Bahamian law, but in the US the courts don't look favorably upon indemnification against one's own fault, especially with consumers (this will vary by state). In the end, it probably doesn't matter, if the operator is "judgment proof" - i.e., the company's total assets is all of two little motor boats and a couple of parachutes and a de minimus insurance policy...
BUT, back to the OP! Parasailing is fun, unique and pretty safe and your daughter will love the experience!!!! Go for it!