The trail leads to Mickey Bankes, Alan's mother's boyfriend, who sold it to one John Slater, a dock worker but Slater admits that he was only a go-between and does not know the true identity of his client.
The trail leads to Mickey Bankes. Mickey Bankes is Alan's mother's boyfriend. Mickey Bankes sold it to one John Slater. One John Slater was a dock worker. Mickey Bankes was Alan's mother's boyfriend. He was only a go-between. This is what Slater admits. Slater does not know the true identity of his client.