I had a hottentota that my dad brought from Namibia. he had caught it in his tent and brought it home to show it to us and I decided to keep it as a pet, it ate at first but then stopped about three months later though it died a month later.
I suspect it was old age . Just make sure they are eating before buying one.
They should be fine in breeding pairs just keep an eye on them and do your research. The only downside is that you can't really tell their age, where as a breeder could tell you how old it is, so you might end up buying an old scorpion. AS long as you mimic its natural habitat I don't see why a wild caught scorpion can't have a happy life in captivity. Just check your local laws about wild caught animals as some places do have strict laws against keeping a wild caught animal as pet even if it is scorpion.
Just make sure you know where it is when you change it's water and wear good, strong gloves as a precaution.