Do you mean in the top left next to Tim in the "Bat" panel? I would not have seen her if you hadn't mentioned she was there. Very hard to see in the print edition because of the way the pages are bound.
The bat symbol isn't all that's missing. She has no facial features, and her hair is colored a flat dark gray that, zoomed out, blends with the cape color. Meanwhile Barbara has worn the Burnside suit, and Supergirl her pre-Flashpoint suit, throughout the series. And Orphan is in the Orphan outfit here. (But was Batgirl in one of the earlier issues.)
Steph was in several panels in last week's "Last Stories" one-shot - no Bat symbol there either.