The closeup image of someone screwing the t-shaped blue board into the case looks like it is the top part of the case inverted (the black part being the tub for the controllers). The t-shaped board is a daughterboard that has the front-led’s (light directed to front via plastic prisms), some power delivery circuits for the charging contacts and a connector for the mainboard which would be at the bottom part of the case (mainboard would have all the external connectors sticking out of the back).