Did you manage to solve this in the end?
The body and foot collider are on the 'Ignore Raycast' layer so I set items on the floor that I wanted the player to walk through on their own layer and turned off the collision matrix tick between this new layer and 'Ignore Raycast'.
It works, the player can walk through objects but there is a pause for a second when the player collides with the object and then they can walk through, for some reason.