Rockwell pressure test?

A dealer friend thought this might be a "Rockwell pressure test" coin, ie some type of drill hole on the reverse. It's a 1938d Walker that NGC graded XF damaged. https://www.ngccoin.com/certlookup/6958797-005/NGCDetails/
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Isn't it a Rockwell Test?
A Roswell Test is something else that involves probes.
Ok: https://conecaonline.org/rockwell-hardness-test-marks-on-lincoln-cents/
Not a Rockwell test - damage, as noted by NGC