[Opinions] Well, but as it isn't pronounced "MAD-uh-len" in French anyway, you can as well... (m)
...pronounce it completely differently in English.
In French, it's mudd-LEN, so that's not even near MAD-uh-len. I think it's OK to just pronounce it like it would be correct in English and not think of the French pronounciation as it won't be fully used anyway by English-speaking people...