HELP! That wily Jack Frost modified one of our naughty/nice records, and right 
before Christmas! Can you help us figure out which one? We've installed exiftool
for your convenience!

Filename (including .docx extension) > 

One of the files seem to contain altered metadata. So let's loop over all files and compare the output of the exiftool helper:

elf@e2533911c94b:~$ for i in *; do echo $i; exiftool $i | wc; done
..
2021-12-20.docx
     44     186    1928
2021-12-21.docx
     44     186    1927
2021-12-22.docx
     44     186    1928
..

So the 21-file seems to be the target:

elf@e2533911c94b:~$ exiftool 2021-12-21.docx
..
Last Modified By       : Jack Frost
..