If she used Larium then it would explain everything.
You may well have a point there. Red Sea area is low to no risk for Malaria, but there was a local outbreak in the Aswan area in 2014, and maybe she was advised to take Malaria tablets. Lariam is known to cause problems including hallucinations and psychotic behaviour in some people. Have a read of this guys experience with it:-
spiked drink and sexual trauma (rape or attempted rape)
Have a read of this which at least gives a timeline to the series of events:-
She fell ill a day into her holiday, but sadly died 2 days later. Drugs used for the purpose of rape are very fast acting, they knock you out quickly. The symptoms she displayed such as hearing voices, don't seem consistent with those type of drugs to me. From what I have read, people have a job to remember much at all after having drinks spiked.