The drop point was south of the Irish coast but from there the trajectory went south south west and given we know that the vehicle got at least as far as staging the best guess is debris ended up a heck of long long way from Ireland.
Something was seen/imaged from the Canary Isles at about the right time which may well have been associated with the launch..
https://www.space.com/virgin-orbit-r...-reentry-video