+1 for getting the spam.
Gmail automatically flagged it as malicious and dropped it into the spam folder.
The Club saying "a small number" is not the same as saying a small percentage.
Even if the hack exposed every member email it would still be a "small number" when compared to, say, the talk talk hack.
Also, saying the email didn't come from the Club server is technically true if you take that to mean the Club SMTP server did not transmit the spam, but that's not the same as saying the Club server was not the source of the leak in the first place.
I strongly suspect the Club server was compromised and the entire membership database has been taken.