I heard this question a number of years ago but have not seen anyone address it. In Chad Gadya we say "Dizabin Abba". "Dizabin" in Amaraic (the language of Chad Gadya) means "that [he] sold", yet according to any of the M’farshim I’ve seen, it means "that [he] bought" which should be "Dizvan", but l’ve never seen a Hagada with that spelling.
As a matter of fact the Hagada of the Yemenite Jews has corrected the spelling to "Deizvein". Rabbi Ro'i Margalit