Spike Jones was a bandleader. He was famous during WW2 for his comic music. He would take serious popular songs and produce parodies of them with 'crazy' lyrics.His band would play them fairly straight but with accompanying sound effects of car horns, whistles, cowbells, crowd noises and anything else that he could fit in. A current TV ad for Schweppes has his version of 'Cocktails for Two" as its music
It's no surprise that Gunner Terence Milligan, with his sense of humour, found a comparison and took the name Spike during the War.
Spike Jones was really Lindley Jones but he was so thin as a child that he was nicknamed 'Spike' because he resembled a railroad spike.