Okay my flight two weeks back got canceled/delayed to an indefinite time.

Anyways I was booked on another airline, so with some encouragement here, I'm trying to earn miles on the airline I was rebooked to.

The issue is my rebooked ticket was basically a paper ticket, so I don't have the ticket number and my credited airline wants that. Any chance I can get this from CX/KA even if the flight was two weeks ago? My boarding pass reads Paper Ticket, so that's of no use.