If that's what she wants to do, that's what she wants to do, if not now, when?
She is an adult, it's entirely up to her, by all means make her take out insurance, you can always do it for her if it bothers you.
My father is in his 70s, climbs mountains in remote countries, has just finished a back pack around south America, is on his way to the Antarctic, He plans to walk across south Georgia, he is a fan of Shackleton, and has a few sea birds left to tick off, he was knocked off his bike by a hit and run car, a few weeks before he left(his helmet saved his life), had to have a couple of operations, he still went, they (step mum) have had a great time in south America, as they always do, in places which people fling their hands up in shock, and say you will be murdered.
on the way to airport in this country, his friend had a flat tire, while he was changing it, they had their laptops and her handbag stolen from the car,
Shit happens here just as much.
When I am in a place that requires local nouse, I send a letter in advance to the local language school, asking if there is anyone who would like to have conversation in exchange for guidance around the local area, and ask them to put a note on their board,
I always pay for all meals and travel, and have found it a brilliant way to get a really good feel for a place,
I have made some life long friends this way, and experienced places in a way tourists never do,
I trained as a documentary photographer so tend to be carrying a lot of crucial expensive equipment, yet have never had a single problem, because I go in with local support.
Name changed for this as it outs me, but I do find it strange when children try to control their parents, at what point are they permitted to live their lives the way they want.
My mother died (cancer) when I was young, but it never made me try to control my remaining parent, he is behaving no differently to when my siblings and I were children, if we were children no doubt we would be walking across south Georgia with him.
She has told you what she wants to do, find ways of supporting it, not sabotaging for your own benefit.