Cabin crew in the UK do not operate with a licence. Training is usually done by the airline itself to the relevant authority's standards.
Medicals are also done by company doctors or by a questionaire, there is no medical certificate as there is with flight crew, and often no actual physical medical examination.
There is no significant cost involved in entering the profession, nor is the salary so high as to justify such cover in my opinion. If one can no longer fly due to a medical condition, but are able to work on the ground, they are likely to earn a similar amount of money as they would flying.
Should crew be unable to work at all (flying or not), then they would benefit from state allowances.