There's no visibility because there's no work.
I'd love to be proven wrong as he's a good software engineer, but he is just not putting the hours. He'll come up with some bullshit saying "I've been working on an update and I'm just about to release it" which is his default answer whenever he's questioned about it by the likes of @therealwolf then he will continue not doing anything.
If he was actually putting in work, why would he not report about it, or at least push the code to the repositories ? Assuming he was actually coding, there is literally no reason for him to be holding off 4 month worth of work and not be writing anything about what's he's working on.