The name Ernst is incorrect. All sources that are contemporary with his life, from birth certificate onwards, show his first name as Ernest. This is what one would expect for someone born in Australia to English emigrant parents; the form "Ernst" is largely an American variant which you would not expect to find in someone of English extraction.
 
The first use of "Ernst" is on his death certificate; this is perhaps an unsurprising mistake as Christmas died in Hawaii (showing 500 of 1659 characters).