I don't think the Matinee was ever released in the Sahara color. It also has the RM script logo stamped into the side, which is something I haven't seen on other Matinees. Ive been doing a little research and asking the resident RM expert (Thanks, GUNG!) and she says that my bag might be one of the "press agent" bags...
I think it's a fairly rare and/or one of a kind sample. It was the only one of it's kind at the sample sale, that's for sure.
...and I will be strong even when it all goes wrong.