Level meter scales -20dBfs RMS

I am calibrating my control room to 79dB for mixing for broadcast. I have the -20dBfs Dolby pink noise file inserted on an audiotrack. (all faders at unity gain). What should my output meters read? The main meter at digital scale reads -8dB peak (orange) and -20dB RMS (yellow). The K-20 Scale meter says +12dB Peak and 0dB RMS. I believe I should use the RMS reading but I am not 100% share. Could anyone shine some light on this matter?

Thanks!