It’s sad that a teacher could possibly have no private life. It’s even more questionable how the account was “found”. I see no one is mentioned as having found it and reported it.
I think it was foolish of the district to fire her; if no student knew about it. The article also neglects to mention parental outrage; so it would seem that not even a parent discovered this either.
If all of this was done explicitly outside of the school, off grounds, and not mentioned ever; it makes no sense other than a few adults finding it awkward.