Radial Engineering ProAV2 Stereo Direct Box

It says "Input - Thru" on top, but where the thru signal come out?

Could this Be used to Output main LR as a separate out into say a Video Camera/GoPro or Phone to get a MONO/Stereo Balanced Mixed?

Can i use all 1/4 input and rca at the same time?(sending audio input from my keyboard(2 x 1/4) and audio input from my usb-dac(rca) ) thank you

Is this the perfect gear if i use vst (pianoteq, kontakt) a lot? from the mac, it can convert to two xlr and for my 2 yamaha hs8 or hs5?