Interesting article. If I may correct a minor detail: By 1968, Sir Matt Busby had not been an Arsenal player for about thirty years. He was the manager of Manchester United.
It was obviously wise for the Beatles never to have released this version. It could have backfired horribly - as satire often does. It is also pretty crude both rhythmically and lyrically.
There were good reasons why a lot of material was never released at the time. Although they recorded several versions of "Have You Heard The Word?" and "What's Yer New Mary Jane", they never made them sound right - probably because they were duff songs to start with!