In 25 years of practice, I haven't seen this happen. Generally the dog may chew on the case, but rarely gets into the flammable liquid. Depending on what liquid is in there, as there are several different possibilities, one needs to know the manufacturer to determine the potential exactly. The government link may help this owner know how to handle the situation. Basically poison control is the answer- so she needs to have the animal poison control number for her area, which she can get from her vet, on hand. It is useful to have it for other issues too, other than lighters. Seven month old dogs like to chew on everything, so make sure she has ample suitable toys to satisfy the urge.
I hope this is helpful.