Has she not got insurance; I assume with the date being less than a week away, the tour operator has confirmed they will a. change the names of the guests and b. do this at no charge?
Just making sure, before anyone goes buying what looks like a bit of a bargain (though tbh, given the position she is in [ie. she needs to sell very quick], she may have to lower the price even further), only to find out they have bought nothing more than some tickets of no use lol. Btw, it's not £250 each, its only £233 - even better!!