"And unless I’m much mistaken, Mostafa is actually attempting to send off the Bulgarian Team Mascots!"
-- Ludo Bagman, commentating during the Bulgaria vs Ireland match
He was the Referee at the 1994 Quidditch World Cup final and proved particularly susceptible to the Bulgarian team’s mascot Veela performances. It was a difficult game to referee and not helped by his trying to “send off” the misbehaving Veelas (GF8).
Leadership and refereeing skills, an unfortunate vulnerability to the siren-like wiles of Veelas
Hassan (حسّان) is a male given name meaning "beautifier, improver" in Arabic (Behind the Name).
Mostafa (مصطفى), a variant of the Arabic name Mustafa, meaning "the chosen one". Both are related to the name Muhammad (Behind the Name).
Lexicon list of Referees
From the Web
Writing by J.K. Rowling on Pottermore: History of the Quidditch World Cup
Harry Potter Wiki: Hassan Mostafa