A belated thought since I seem to have missed the discussion here as it occurred.
The following translations, none produced by the WTS, have "to him" or "the one/the one whom" here:
James Moffatt (1935), Smith-Goodspeed (1948), Jerusalem Bible (1966), New Jerusalem Bible (1985), Today's English Bible/Good News Bible (1976), New English Bible (1976), Revised English Bible (1989), New American Bible (1970, rev. 2010), Contemporary English Version (1995), English Standard Version (2001), RSV (1952), NRSV (1989), NRSVue (2023), Common English Bible (2013).
Surely these translators, trained in the ancient biblical languages, in the problems of translation, and in the ancient world in general did not feel they were doing anything questionable or blamable.
Of course, a few do render the Heb here as "to me," but they are the minority (KJV, Rotherham, NIV, NASB, HCSB), and while The New Jewish Publication Society Tanakh Translation Study Bible (2007) has "to Me" in the text, the commentator clarifies that rendering by the following note on this verse:
"The Heb is ambiguous, because it may refer to a person or group whom they have pierced. Although the identity of the pierced one/ones is unclear, if the text is read as the continuation of v. 9—as the structure of the section set by the in that day openings suggests—it is more likely that it points to an individual or group from within the nations." p. 1264.
It is wise for someone who is beginning to study the Bible seriously, obviously outside of what is spoon-fed at the org's meetings, to be cautious and not quickly jump to any conclusion about the org's mistranslating/corrupting this or that passage when some inconsistency is first perceived by simply looking at different translations. There are so many passages with difficulties and ambiguities in them that the wise course is to find out first whether a given passage is one of the many that has problems. Certainly this is one—as history has made clear.