I did a quick scan of the character list on Lostpedia and didn't see any characters with the initials "R.G". No surprise.

The past characters with a last name beginning with "G" were:

Horace (and Olivia) Goodspeed - the Linus' friends from Dharma

Henry Gale - we don't know much about the real HG

Janelle Granger - keeper of the diary on the ABC website

And we're meant to assume that the Elsa's bracelet was the same as Naomi's, correct? That seems logical because the backer behind both seems to be after Ben.