Can anyone help?

I was told earlier today that the Filipino wife of a British national, living in Spain on a permanent residence permit, was not permitted to fly from Cebu to Madrid because, although she had a Visa (for settlement) and the CFO sticker with permission to leave the Philippines, she did not have a return flight ticket.

I have another friend whose wife has a single ticket to fly to Spain from MNL on 2nd May. We want to avoid any similar problems.

Any advice will be appreciated.