As Rya indicated, the contributor category includes those who have made "significant contributions to the game of basketball". For a list of contributors, see
here. At a quick glance, it doesn't appear that any have gotten in due to charity or humanitarian work.
If the Hall allowed recognition for humanitarian work, Dikembe would be a clear-cut inductee. However, I'm not sure that they do, at least the way the rules are currently construed.
Interestingly, I just found out that Satch Sanders got in the Hall as a contributor, rather than as a player. It seems like he made it in largely as a "catch all", and I can see borderline players like Dikembe get squeezed in this way, even if they don't meet the strict criteria for induction.