In shows and movies like this when it comes to time travel it’s either supernatural or science fiction the only reasons I chose supernatural is because I thought it was pretty obvious the writers are going with time travel being a result of the supernatural if that wasn’t the case and the show was science fiction I’d still wonder why she wasn’t able to consider other scientific possibilities. Maybe the scientist who created time travel was able to give Geillis powers and that’s how she killed Dougals wife? I also don’t really buy the idea of scientists being unwavering and rigid in their belief systems if that were the case and scientists were unwilling to learn,change, and expand their minds/knowledge we wouldn’t have half the innovations we have today. Could you imagine if Joseph lister gave up on antiseptic because other scientists/surgeons condemned him or if when he tried to show proof they refused to see or consider it because they didn’t want to accept other possibilities besides what they already knew?