renebur welcome ,glad to see you are involving your son at an early age.
Just bear in mind that it is winter and taking your son up in the mountains one must be very prepared at this time of year, no matter if you decide to take a tent or stay in the cave, i always have a tent with me you never know what the weather will do.
As from a security issue it is a long weekend so one must be on extra guard,but been winter the risk is definitely less, in my opinion ,i always remain polite and friendly when i encounter locals.i am also sure you will see other people up there too if you do, just ask if they don't mind if you camp close bye the more eyes and ears the better.
The other thing is that the cave is not far of the main path and should there be locals using the path and seeking shelter you might find that you will have guests.