Poole states that by adding water to the lime that the headmaster had used to build his patio it changes to slaked lime or quicklime. However these are two completely different substances. The headmaster would have bought slaked lime, a common building material. Quicklime is calcium oxide and is produced by heating limestone, or a similar mineral that contains calcium carbonate, in a kiln. Adding water to quicklime produces slaked lime, calcium hydroxide. Quicklime cannot be produced by adding water to lime.
Camille, who is an experienced detective sergeant who graduated at the top of her class and was trained in Paris, shouldn't need an explanation of the well-established method of using cyanoacrylate mist to obtain fingerprints.
DI Poole (Miller) is very quick to dismiss the fact that the victim predicted her own murder using voodoo. Whilst he may not believe in voodoo, her claim could have been based in real world circumstances. His dismissal of her claims and instructions for it not to be discussed could lead to some evidence such as phone records or written threats not being explored.