AP put Ninja of the Deep Hours onto battlefield with its ninjutsu. After combat damage and its triggered ability resolved, can AP return it to their hand for another ninja's ninjutsu-cost?

I think no. Because when the turn-based action of CR 509.1h occurred it wasn't on the battlefield, therefore it isn't an unblocked creature nor blocked creature. But several judges say it's an unblocked creature and legitimate for ninjutsu-cost.

I would like to know official answer.
Thanks.

EDIT:
Soon later I posted, Justin Pursell san told me a relative CR. That reads:

702.48c A ninjutsu ability may be activated only while a creature on the battlefield is unblocked (see rule 509.1h). The creature with ninjutsu is put onto the battlefield unblocked. It will be attacking the same player or planeswalker as the creature that was returned to its owner's hand.

Justin san, arigatou-dattebayo.

Edited Takeshi Sue (June 23, 2019 07:48:36 PM)