There's no way they can offload Kemba unless they add in something else of value (like multiple 1sts or hell, a player like Jaylen), or take back another albatross. Even bad, small-market teams that can't lure stars would probably stay away from Kemba unless they were incentivized in some way.
Yeah, a Kemba trade is possible through S&T or having his salary involved in a bigger deal, but if that were the case I imagine there'd definitely be a lot of moving pieces. It's just not that simple to "offload Kemba"