I don't think it's overstated. It's ridiculous that it's happening in what's supposed to be the premium venue in all of tennis (with apologies to Centre Court), in the first place. Murray was looking good on that point - he wasn't 100% to win it, but he was in an advantageous position, hitting a ball to a corner that Nishikori had real trouble getting to as play was stopped. But most importantly, Murray let it get to him. He lost 12 of 14 of the next points and quickly pissed away the set and then went down a break early in the 5th. Murray had been in incredible mental rhythm in the last parts of the 3rd set and early going in the 4th, and that totally destroyed his focus - he went up to Cicak in the chair and angrily said something after the next point, and then called out the tournament official on the next changeover.
Anyone who missed the match and wants to watch one hell of a set of tennis, watch a replay of that 5th set. Just some incredible work by two of the fittest players on tour going through their fourth hour of play.