Hi Mike,
As I remember it, (and it was a few years back !), in 1978 Wigan was at a low point in every respect. Musically the scene had drifted first to Cleggy then St Ives, then Yate & R.S. was the only one left flying the flag at Wigan while others were playing the likes of Joe 90 & rubbish british pop like stuff. There was also the barb epidemic.......
Numbers were dwindling apart from the monthly oldies nights & the management made this Billboard top disco up as one of many publicity stunts to try & get the numbers back up.
I remember a conversation around that time in the dressing room to the back left of the stage as you look at it involving several several people (heavily involved with The Casino management) who were openly laughing about it being a ruse. I'm not going to name names - as I say it was a long time ago & only one person persists in perpetuating the story.
That's the reason I have never believed this story. If anyone can produce evidence to the contrary I'm happy to eat humble pie & say that the conversation I heard was the ruse, but I think I'll be having a long wait.