They won't let you in without a ticket. In 2013, my friend lost her ticket and showed her print out confirmations, bank statement and all that jazz to the people at the box office & each of the gates but they were firm they wouldn't let her in. Hope you get it sorted! I would probably keep on at Royal Mail and if your mate sees their postie maybe they should ask if they remember delivering a Special Delivery Guaranteed by 1pm letter on the day it was 'signed' and where?