Isn't that backwards? The nonexistent character is in the -digitized- version so presumably OCR or something got 彊 wrong, that's not saying that 彁 was used in the -print- version.
Indeed, the source link is about exactly this: a crappy scan appears to have 彁 but a better copy reveals it was 彊.
I think you're both saying the same thing: the digitization of the article wouldn't have been the source, since 彁 would have had to exist before the digitization happened in order for the OCR to misread 彊 as 彁.
Most kanji are a combination of several smaller parts called "radicals" in English. If you look at these two kanji through this lens, you will see that it's actually a very simple mistake, one existing radical is replaced by another existing radical. It is very easy to imagine software that was working exactly like that: interpreting kanji as a combination of radicals rather than individual unrelated symbols
This reminds me of the pregnant man emoji [0] but it turns out they decided to handle that in an unusual way [1] so not really.
[0] https://emojipedia.org/pregnant-man
[1] https://www.reddit.com/r/technology/comments/u7x3l9/comment/...