No timing, sir!

I had this interesting conversation with a security guard at Citibank. I was there to meet someone regarding my new bank account. The guard went in to check if he was there. He returned soon, and then the dialogue went something like...

"No sir."
"He's not there?"
"He's left outside."
"You mean he has left for the day?" (It was 4:30pm, reasonable likelihood.)
"No sir, he's left outside."
"Ok." I was about to leave when he stopped me.

"Sir, he's coming."
"You mean he is still here?"
"No sir, he's left outside. He's back."
"Uhh... He is out, but he is coming back?"
"Yes sir."
"When?"
"No timing, sir."

Needless to say, I left.