The obvious choice is that LeBron is talking about Kevin Love who hasn’t been fitting in great with the Cavs even when they are winning.
It was LeBron who wanted Love over Wiggins, so if that is who he is indeed talking about he needs to handle that man to man not through subtweets. It is possible he is talking about someone else entirely. Normally, JR Smith would be the culprit, but everyone seems to love JR in Cleveland and he is fitting in quite nicely.
Don’t leave us in suspense LeBron tell us what you are really talking about.