Photo: What is this Strange Light Captured at the Evansville Country Club?

Look closely at this photograph. What in the world is in that window of the Evansville Country Club? This was taken by A2 Photography, without a flash, and it only appeared in 2 of the photos. It's very important to note that this room isn't even a real room! This is what the photographer, Ashley S. Ashley, had to say about it;

Okay friends, this is the Evansville Country Club. I was taking portraits of the guests and the event person asked me to go out and get a shot of the projection and some decor.
I was editing in the dark when I saw this! 😳 I did not use a flash (everyone asks that but a flash on a window doesn’t look like that anyways). It was in two shots and none of the others.
I didn’t see it while I was shooting.
The building is over 100 years old, the employees all swear its haunted, and I found out this window isn’t a room at all they did a renovation and it was boarded up and dry walled so it’s not something inside of a room.
What do you think?!

Here's a zoomed in version. What do you think it is?