Oh give it a rest.
Nobody cares when a President goes to a State Funeral for some other respected world leader.
They whined about Biden's hotel bill when he went on an official state trip to Europe to negotiate with European leaders over what course of action to take about Iran's nuclear weapons program.
Of course, they made no mention that that was the actual purpose of the trip. All they mentioned was the hotel bill.
They whined about Obama's bill when he went to an economic summit in Ireland. And he stayed at the exact same place Bush did when he went to an identical summit seven years earlier!
Of course, they made no mention of any of that. All they mentioned was the cost of the trip.
And who can forget the last time Obama went to Africa and all the whining about the cost of that trip? Even though the purpose was foreign relations, which is the primary job of the President. What do the whiners call that trip? Oh, yeah. "Obama's African vacation".
Thus it is to be expected they will whine about attending a funeral for a world leader. So I'm okay with someone pre-empting their piss party.