Aurender seems to me to be very careful to be purposely incompatible with Roon, which they see as a competitor. Aurender was on my short list until I figured this out. I went with innuos....
However, I think it is best to have your core on a stand alone NUC. I have a spare one I'm getting ready to sell if you are interested. I put ROCK on mine and it works great.
But I don't think your Aurender will work as an endpoint...I haven't tried it. On several stramers that I have tried, they are "pass thru" to Roon and Roon sees the DAC, rather than the streamer. Perhaps this might happen with Aurender but based on the frustration I've read from others, I suspect it won't work
Jerry