At the temperature of melted wax, kerosene is too volatile and would form a vapor cloud over the wax. It has a flash point of about 100°F. If you are heating wax to 200°F, as propose above, that is significantly above the flash point of kerosene. Paraffin lamp oil has a flash point of 200°F. That’s still a bit low for a 200°F wax melt but better than kerosene. Mineral oil has a flash point of 440°F. Much safer. Vaseline has a similar flash point to mineral oil.

Almost all of us are familiar with liquid solutions. Sugar in water is a liquid solution. A cocktail is a liquid solution. Whether we know it or not, we are also very familiar with gas solutions. We breath it everyday, all day long. But we are far less familiar with solid solutions and how those change things like viscosity and other physical properties. Jelly (not jam) is a solid solution. Sugar, water, pectin and flavorings are mixed together under the right conditions and can be made into a homogeneous solid (or semisolid) mixture. Water have a low viscosity but add sugar to it and the viscosity goes up slightly. Add in some pectin and the whole mixture can be made to be almost solid.

Adding something to the melted wax won’t make the melted wax more liquid. It will make the hardened wax more liquid. Or, more specifically, it makes the wax less hard.