Small company availing of unpaid work experience person in the near future. Looks like their role will involve much of what my friend is already doing (which is varied) and they will be required to train them.
Their fear is that once the new person is competent my friend will simply be let go (company not doing well) and role taken over by the temp (who if and when made permanent, will be employed for less money)
People are not made redundant, roles are, therefore if your friend was let go simply to allow a cheaper person to do the same job, she could have a case for wrongful dismissal. (assuming your friend is in perm employment).