Sounds exactly like a guy I work with. He's a prima donna too. Persistently reinvents the wheel (he's one of those "my wheel is rounder than yours" types) and implements these convoluted solutions to problems that he can't really explain it, or find time to explain it. My philosophy is that if you can't explain it to me, in layman's terms in under 3 minutes (you're allowed a whiteboard), then you can't explain it to a computer. Unfortunately the directors don't see it that way (he's an arse-licker of note) so he gets to implement these horrific solutions which are so much more complicated than they need to be (he prefers to code "impressive looking" over "functional") and which will be completely impossible to maintain. One thing he has taught us all though tho, is how to be a complete self-aggrandizing tosser. He's so toxic that the coders around him are starting to resign, he's impossible to work with.
I take comfort from the fact that I did warn them that this was the kind of guy that he was when he first started, and they didn't listen. The company has turned from being a happy "family" to one where everyone is covering their asses, stealing credit and stabbing each other in the back, just to maintain their positions. I'm leaving too.