ORLANDO, Fla. — Miami Heat assistant coach Caron Butler is watching the organization’s G League affiliate, the Sioux Falls Skyforce, a little closer these days. That’s because the Heat’s developmental affiliate acquired Butler’s son, JC Butler, from the available pool via roster hardship last week. JC, a 6-foot-5 guard, went undrafted this past summer out of UC Irvine before arriving to the Skyforce. “It’s amazing,” Butler said ahead of the Heat’s matchup against the Magic in Orlando on Wednesday night. “I’m forever grateful to the Arison family and coach [Pat] Riley, Andy Elisburg, coach Spo …