You will probably find that the alternative flights will be paid directly by the licencing / bond authority. In the Uk its the CAA, through the ATOL protection scheme, of which any uk airline/tour operator must be a member. - I presume the US authorities have a similar system. My company has been chartered directly by the caa several times in the past, to operate repatriation flights.
.....Only if operating as a package holiday. As with any airline (unfair in my opinion as tour op's do!) they do not need to be part of the ATOL scheme.
Good luck to the staff though, hope they find new employment soon.