From the tracking site it seems they already turned back... if not I would continue downwind and down current to the Cape Verde islands for a repair. Presuming repair is impossible, would it be possible to lash the boom to the deck and sheet the main loosefoot as this is a downwind ride... repair in Bridgetown.
I did this run in 2006 and we used the main sparingly as the genny brought us to hull speed most of the time, thus the loosefoot main and genoa should be enough all the time.
Pierre