Boundaries that are placed would be done in such a way...
If nervegear existed would people use it to evil end like in SAO (Sword Art Online)
Boundaries that are placed would be done in such a way that loops holes don't exist, we'd remove the feature that death of the living person happens on the death of the virtual character, therefore preventing the possibility of someone even dying. People are going to notice how you kidnap someone, why not just save time and take the person directly. If you left someone trapped inside the game world with the chance of them dying, wouldn't that be a tad dangerous. Nervegear would only ever bring good to the world, as no one would be able to change the system programming if the right measures were put into place. Say weekly patches, frequency of use databases, and other kinds of defences would be used to prevent someone being trapped in the world. If someone were evil they wouldn't waste time sticking someone in a virtual reality, they would have to place the person under severe surveillance and that would mean getting others to go along with the plan, meaning that it would be that much less subtle then just simply kidnapping the person directly.