Umm, the Dragon Rune, Beast Rune, Sovereign Rune, Night Rune and Blue Moon Rune seem to have no lesser rune, so I'd say that it probably isn't safe to assume that all True Runes have a lesser rune. Also, we have not seen a possible lesser rune for the Rune of Punishment.
Sorry to nitpick, but I'm just saying that it's possible that the blinking rune is just a personal rune for Viki and it's possible that more than one can hold it just like Stallion was believed to be the only one with the Godspeed Rune. If we go by that logic we would have to say that Jeane's charm rune is possibly the lesser rune of the True Charm Rune..which is possible.
Also, the Night Rune seemed to allow blinking ability, as well. So, she doesn't really have to have a True Rune. Konami is always quite close-mouthed about releasing information about their series especially about that type of information. They wouldn't email such information that they would rather show in their games. Sorry for the detailed responses, I'm just giving a difference of opinion.