I've posted this previously regarding the origin of dances but it seems that it needs to be repeated. There are two loose categories of dance as far as the ballroom dancing community are concerned - Ballroom & Latin American. The latter refers to Latin AND American dances. Charleston, Lindy, Ballroom Jive & Rock n' Roll are members of the family of dances that are referred to as American (If you want to get picky Quickstep could be as well as it decends from Charleston / Shag as well as Foxtrot).
It's worth noting that the Charleston predates The Quickstep & is close the same age as Foxtrot. Lindy arrived way before Cha Cha Cha / Rhumba / Jive so any discussion of "traditional" dances is a very moot one.
My take on it is that Charleston is Latin American so fair enough BUT as Ricky never had the opportunity to dance it, I don't think that it is entirely fair for COLA to be able to repeat it (likewise RnR for Ricky). However at the end of the day it is only a light entertainment programme