In this day and age any successful performing Hypnotist will have insurance.
If you’re looking to hire a Hypnotist, ask if they have insurance. Not all do. If they don’t well, it’s your decision. Do you drive your car without insurance? Do you hire a tradesman to come into your home to renovate that isn’t insured?
Insurance varies by location and facility. Facilities all have insurance and sometimes they cover all aspects under their policy. Sometimes they don’t.
It is your responsibility to verify that the Hypnotist has insurance.