Over the past few years we seem to get that question more and more. The best source for information about former patients at the settlement is http://kalaupapaohana.org
They are a nonprofit organization formed in 2003 that is dedicated to promoting the value and dignity of every individual who was ever exiled to Kalaupapa beginning in 1866.
Use the the contact page – kalaupapaohana.org/contact-us.html to email them your ancestor information request. They can provide information that should get you on the path to finding any ancestors you might have had at Kalaupapa.