Great at shielding the ball, never looks up afterwards

I would connect the shield to a purpose. At the moment he may see protecting the ball as the end of the action. Give him games where keeping it for two or three seconds creates a new option: a teammate moves, a gate opens or a target becomes available. Then ask what changed while he was protecting it. You can also encourage a quick look before the contact arrives. If he already knows where space or support is, he is less likely to spend five seconds protecting the ball with no next idea. I would keep praising the ability to use his body. That is valuable. The next step is helping him recognise when to release, roll away or turn once the protection has bought him time.