Great question — answering as the UphillTech team:
I bookmarked this question because I was curious what the final answer was. It looks like there has been an impasse on the discourse. In my research, I was led to Mark T. Denucci Sr. https://forum.officiating.com/basketball/3757-referee-part-court-court.html#post33623 Crew had it right--R4-4-4 in Fed book.Casebook 4-4-4 is relevant,too. I agree with Crew and the above Rules and Casebook references. But I do have one problem with the official catching the ball in the original posting. If the official is inbounds when he catches the ball, we might consider the ball becoming dead in this situation and have to go to the dreaded AP Arrow. He had enough of an online presence for me to go through...
Full answer by user32355: https://sports.stackexchange.com/a/29948 (CC BY-SA 4.0).
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