I would have taken a safety shot to exclude the strong light entering. When the light meter sees that much light it will underexpose everything else. Just repositioning yourself OR taking a metering reading of the room and at the same time use exposure lock you could get an even exposure.
The idea is fine but the image is underexposed because of how you metered the scene. Even some fill flash may have helped but that flash would have to overpower the Sun.
Their is an even more involved method but then it really turns into a photo shoot.
Not sure if it occurred to you, but that might well be exactly the look and mood that the OP was going for in the shot. I liked it, and while it was technically underexposed, that dark look made it that much more interesting, at least to me.
I liked the images a lot... great eye.
) to get the best out of it.
