Late to the game here, but you don’t need the matrixbrute or the reamp box to send stuff out of the computer into pedals. All you need to do is turn the level down on the audio interface output, so it doesn’t clip the input of the pedals.
You only need the reamp box if you are sending the output back through a long snake (to help with noise from long cable runs), or if you are using a vintage fuzz or wah pedal that expects to see a high impedance source (guitar with passive pickups).