Why was Tavon written out the show?

What happened with Tavon?

He was introduced late in season 2 and was developing into a really good character. Then came that utterly brutal showdown with Shane (and Mara).

At the time I was sure he was dead, and it was one of the most shocking things I'd ever seen on t.v, mainly because how it just happens in the blink of an eye.

But then it turns out he survives, but is written off the show, until one episode towards the end of the show, just to show that he is at peace with what happened.

So what happened? Did the actor have other commitments? Keeping him alive kept the door open for a possible return I guess, but interested to see if anyone knows for sure what happened.