It's very interesting to find this possible Hungarian link - even more if it could be confirmed.

Garry: punctuation can change the meaning of words, inside of songs or outside. Correct punctuation is as important for communication as grammar, syntax, or any other part of the language. I still think that the line
"but never yet you heathen dog" benefits from a comma, the written equivalent of a vocal break for rest, or to separate ideas
"But never, yet you heathen dog" gives us the phrase "yet you heathen dog" which is gibberish. "Yet" has no meaning in that phrase Yet what? The phrase cries out for completion.
"but never yet, you heathen dog" seems to be better English, with both halves meaningful. Well, the first phrase is perhaps more poetical than a particularly good construction, but it does get the meaning across.

Sorry if this seems excessively pedantic to you.