I don't believe that it could have been suicide. Even if the claims are true, there is no way it is something Jessie would do.
She had her whole life before her. Jessie was a real fighter. She was bubbly, clever and considerate. I don't think she would have done this to her family on purpose.
However, a report in The Guardian still maintains the suicide angle. The paper is relying on statements made by Czech police. A local police inspector was quoted:
We found quite a lot of medication, a lot of vitamins and then things we could not tell what it was until they were examined by medical people and they found they were antidepressants. They were in her name. We think she may have had psychological problems. It could have been an accident. But there are several factors which suggest she probably jumped.
Aside from the main story of Jessie Gilbert's death, there has also been the occassional mention of Jessie's drinking spree with her 14-year old room-mate Amisha Parmar. I wonder, is this sort of thing common amongst under-age chess players, especially those who travel overseas, away from the supervision of their parents?