The Draft Instructions specifically tell taxpayers that they can look it up using the first link that was given above.

Personally, I think I am going to ask the clients to give me either (a) both 1444 forms, or (b) a printout from that website dated AFTER January 15th (the last date the IRS can send out advance credits for the second credit).

I may accept their verbal amount if they say they received the FULL credits for BOTH payments.  But if they claim less, I want proof.