why would he need a broker for such a regular straightforward trip?
Its not obligatory is it! I appreciate if you're shifting Kylie around a world tour then a broker will come into his own but a regular flight like this theres considerable savings to be made over 12 months if you book direct and it might be the difference between the client actually doing it or not doing it.
A broker might be handy for the operator to find some work for a regular Ibiza based weekend aircraft for an out and back - in fact that might be handy as long as you're back for Sunday night