I may be wrong but from what I have been told, if an MP dies in the H of C, the place of death is recorded as the hospital where the death is certified.
if this is a question from a quiz (I'm guessing, but it's been asked before), you'll get many more answers posting it under Quizzes & Puzzles, since that's where quizdoers hang out
We found out that a former owner of our house, the death certificate was in our deeds, died in the next village to us, this was because he died in the ambulance there on the way to hospital!