I don't know for sure, but it does make sense that if you were in building 35, that 3519 would be the room number
Good morning, son
In twenty years from now
Maybe we'll both sit down and have a few beers
And I can tell you 'bout today
And how I picked you up and everything changed
It was pain
Sunny days and rain
I knew you'd feel the same things...
Is it a Key to the World card? They have never had their number printed on them. 1996 is the year the ticket systems were re-done, so it's hard to say for sure if you had a "Key to the World" card or not. Do you have a photo of the card?