Upvote:2
I am going to catalog the results above because comments sometimes get deleted, and are not intended to be part of the permanent record for a question.
Update - from an anonymous contributor:
Charles O'Mahony in the 1930 US Census Bronx NY is my mother's uncle. He was married to Helen Zacbek. He was born in Nenagh, Co. Tipperary, Ireland 1881 and died in the Bronx NY 1942. He is not Charles Kingston O'Mahony.
Seamus Murray Dublin