There are so many variations of name spellings, it's ridiculous, but it's the same guy.
Dr. Waleed/Walid Abdul Khaliq/Qaider al-Obeidi/Obaidi.
I believe the last name al-Obeidi means he's from the nearby town of Obeidi.
Haditha Hospital Director/"Chief"
It's difficult to get the arabic into an "Americanized" translation, and names are usually translated phonetically by whomever is doing the interview. Thus the different variations. My understanding is the bad guys use this to their advantage, as they can point to the watch list and say, "My name is Muhammed Obami, not Mohammed Abami."
No doubt in my mind the "good doctor" at the Haditha hospital is an al Qaida sympathizer, and the one who listed the information on the death certificates. He had had many run-ins with the Americans before, and obviously has no love for them.
Enormous grain of salt in using this very same doctor's death certificates as proof positive that the Marines are cold-blooded assassins.