Well consider there's a roof and no definitely light source, except the open fireplace in the center of the communal room. Halo shadows work well for VT purposes, instead of directional shadows, as light source changes and shadowing changes. Placing shadows here simply amplify where the walls are and and which objects are a part of the floor and which are above it.

Depending on my needs, I use both directional and halo shadows.

So I see no problem with using a halo shadow for the interior.

GP