[quote=@thewizardguy]
Why would he not be able to board the plane? Does London prohibit vampires from boarding planes?
[/quote]

The issue isn't why he would be unable to board the plane my friend.
Any vampire can go board a plane, nothing is stopping them, it is not like Bedivere keeps tabs on every single existing person in his country to the point of knowing every bit of information about them. No, this is a task for entities, not singular beings.

Rather the fact that he had boarded the plane as a vampire which shall cause international incident.
Hence the implications after the event is Bedivere's issue. Not the event in itself.
On the political level, it would cause intrigue and cast a negative light on the state of the Isles.
As such, Bedivere would not enjoy the international attention.
Now he has to clean up the mess... By perhaps making more of a mess.