It's a biblical name tho a very unusual one - never seen it used before (Moloch was the god of retrograde idolatrous Judah in the wicked King Manasseh's generation) - I have Quaye, Manasseh, tailor & draper, Charles-street Peel in 1882 directory + similar entries to 1887.
Quay,Quay,Kee + Key are all variants of same name - see www.manxnotebook.com/manxnb/v07p114.htm