Returning Expired I-94 Slip In Person With Proof?

[Hakka90]

I know the border website states to return the I-94 slip with proof of return before the B1 visa expired but would it be possible for me to go directly to the nearest airport to visit US customs officials and return this slip with proof that I returned to Canada before it expires? Specifically at the Pearson Airport. Or does it have to be mailed to the Ohio office? Thanks.

[immihelp]

You can't go to the US airport later and submit it.