I wonder if removing the hyphen would help:
Firstname Georgeson Johns
OR
Firstname Middlename Georgeson Johns
Then if the whole lot is too much of mouthful, s/he can always drop one of the surnames for everyday use (but would still have both on official documents - birth certificate, passport, bank accounts etc)
I have two surnames, no hyphen, and I do drop one name sometimes (for hairdressers and restaurant bookings and things like that)