Facing the first coast-to-coast live Billboard Music Awards, NBA and NHL playoffs and a little show you might have heard of called Game Of Thrones, AMC had a busy Sunday night with the first midseason finale of Fear The Walking Dead and the premiere of Preacher. On the whole, the former home of Mad Men held up OK with The Walking Dead spinoff series steady with its Season 2 May 15 show and the Seth Rogen, Evan Goldberg and Sam Catlin EP'd adaptation of Garth Ennis and…