I opened my personal checking account online using the link within the coupon. At the end of the application there was confirmation of the 25k mile offer, but I was not asked for my OnePass number anywhere.
Do I need to contact them to have the account associated with my OnePass membership?
Give them a few days and they will "usually" divine it on their own. Log in to chase.com, click on "show rewards" and then the account to get to the "Show Details" screen. It should list your Onepass number there but may take 4-5 days to show up.