OP here.
So the online bag tracking system automatically updated SFO-EWR-ITH to SFO-EWR-SYR.
It showed the checked luggage as offloaded from the plane EWR, but then the status updates stopped there (i.e., EWR-SYR flight took off, but luggage did not show as on loaded onto plane).
Daughter landed at SYR, and as it turns out, all the checked bags put on plane were supposed to go to Dallas. No one on SYR flight received their checked luggage,, because apparently they all stayed behind in EWR.
And also, Dallas passengers will be pissed to learn that their luggage is in SYR.
Perfect storm of screw-ups.