Calibrate in the daytime. Just close the blinds while you're doing it.
And you'll need to only edit in the daytime, until you have brighter lights that match daylight.
Yeah, you're not the first person to mention this glitch. It's very annoying. Have you continued on to complete the calibration; and if so, how was the print match?
Oh, right, I understand now.
This is just a simple matter of Levels. Select that dark area, add a Levels layer and clip it to the cat layer, then use the black eyedropper to get the weight right.
https://www.damiensymonds.net/levels-eyedropper