S04E02 "Negative Reaction" question...

About three quarters into the episode, Columbo visits Paul Galesko (Dick Van Dyke) to show him pictures he took at the cemetery, the "phantom accomplice" theory. Columbo tries to trip him up by adding, among the pictures, a picture of Mrs. Galesko tied up near the fireplace where she got shot, a picture that Paul Galesko took. It's a long shot, but I guess Columbo was hoping for, "Hey that's the picture I took before I killed her!" LOL! Here's my question... When Galesko sees the photo he took, he has to play it off, but was his reaction normal? He didn't say something like.. why is a photo of my wife here? Nor, did he put up some sort of emotional fakery. I mean that's a picture of his wife tied up by the fireplace, the moment she was murdered. Shouldn't he show a little sadness, crocodile tears? His reaction was a nonchalant "what's this one?" As if he doesn't even recognize who the women in the picture was. Columbo and Galesko goes on to critique about how bad the picture was. That scene just doesn't make sense to me. Is it just bad script writing? Please go back and watch it if you guys have it, and shed some light. Thanks!