Looks like you have a face lifted cls, like mine, the original had an ashtray in that location in the rear door, and I believe is now used if you have the harmon karmon upgrade
2003 W209 CLK, 2005 R171 SLK, Volvo XC40 P8 Twin Motor Pro EV
I had a similar surprise with the CLK. Removed the grilles off the parcel shelf only to find no speakers. Probably they only fit them with an upgraded sound system