The lens has thrown his own rays which add brightness. The image(see NOTE1) is still there except where overexposure has happened. You can add darkening rays (No, I'm not sick). They are easier to insert and adjust in Illustrator or Inkscape. You draw blurred dark grey lines which have blending mode Darken. The color, blur, opacity, stroke width and placement need adjusting. An example:
A = a copy of the inserted line bunch without blur effect
B = like A, but gaussian blur effect is added.
You can add new lines by dragging and holding alt at the same time. That makes possible to build the darkening bunch gradually. Lock the photo to prevent accidental moving.
NOTE1: You will not get perfect results. The faces have poor contrast and that cannot be boosted without pushing the noise and the remnants of the flare. By careful darkening you can reduce the flare substantially, but the needed work also is substantial. It can be justified by the fact that the image is really taken, not a composition where people has been inserted into the image.
NOTE2: Blending mode darken probably isn't optimal because actually the flare rays have different color than the indoor light which illuminates the faces. Blending mode subtract would thus work better and the rays which are subtracted should be the light. The right color can be picked. My software hasn't blending mode subtract.