Exactly how confusing could it be? There was a tag attempt of the runner sliding into home and an umpire would NEVER announce a runner had not touched a base, so by calling no tag and giving a safe signal it should be pretty obvious exactly what the umpire is calling.
I thought the mechanic for the OP was a slight delay, to see if there was another tag attempt or runner going back to touch the plate, followed by a safe signal.
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