Strictly, it doesn’t melt at 68. It melts at >68, and (although I’m a chemist I’m not a H&S / data sheet expert) I suspect that has been chosen as a threshold for flashpoint / flammability measurements. ie: if it is not liquid at 68C it doesn’t flash at that temp and therefore doesn’t need labelling (might be wrong)
It’s like saying Sale! Up to 50% off, and then finding the jeans you want are 5% off – that’s ‘up to’ 50% so legit. >68C might mean it doesn’t actually melt until 120C, or 2000C, they’re both >68C
If we knew what the base wax wax this might help, but the reality is that i suspect it won’t be an issue even on a hot Aus summer’s day.