Good question.

I haven't tested that but I think it's possible to modify the fragment with Javascript: https://stackoverflow.com/a/4282075

So my idea would be getting looo.ong to create a special client-side redirection webpage that would remove the fragment part using Javascript before performing the redirection with Javascript. And no. Using HTTP redirection response on server side won't work.

EDIT: I've actually seen URL redirection websites that removes the fragment part so it should be doable. Perhaps the purpose of that is to avoid spam abuse.