Most of my mind thinks its suicide, but I just can't get past these two details -
a) The meal she ordered the night before still being undigested in her stomach.
b) The lady who delivered the meal the night before saw a small suitcase in the room and 'Jennifer' wearing garments not present after her death, despite the key card not being used to enter the room again after the time of the meal being delivered to the room. Where did these items go? How could Jennifer have disposed of them without leaving her room and therefore having to use her card to get back in?