Huh? I've been arguing precisely that Mr Oswald did say he met him on the 1st floor------in the 'vestibule'!
Sequence of events!
1. Mr Oswald breaks for lunch
2. Mr Oswald comes downstairs
3. Mr Oswald buys coke in second floor lunchroom
4. Mr Oswald comes back down to first floor to eat lunch
5. Mr Oswald goes outside to watch P. parade (and shows up in Wiegman film standing just behind Mr Lovelady)
6. Mr Oswald has (benign) encounter with Officer Baker & Mr Truly in the vestibule (front lobby)