You can call local unit support, but I tend to doubt if the church has the information.
Depending on the country, I would expect the donation slips and ward-level paperwork to have been destroyed by now. (In the US, anything prior to 2015 should have been destroyed). I'm not sure as anyone would keep records beyond 10 years unless required by law.
Depending on what year you're talking about, the donation may not be connected with the membership number. And individual donation may not have been transmitted to Church Headquarters - only batch totals.
At any rate, local unit support should be able to help you give the member some kind of answer. I'm sure there must be some kind of "statute of limitations" for correcting errors - and I'm sure that's long past. Just as reference, it appears that notifying a bank of an error on your statement is only 60 days.
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