lots of motherboards will fall back to SPD ram speed and timings if memory training fails... we need to test if that is the case.
reset bios to defaults if you haven't already tried that.
consider testing the ram with something like memtest -
https://www.memtest86.comthen...
test 1:
then set the xmp as you have, which will set timings, speed, and voltage, but this time lower the ram speed to say 3200mhz and see if that works. If it does, then step it up in increments until it fails, and we'll see where it lands.
test 2:
set the uclk/mclk divider to 2:1 (i.e. uclk = mclk / 2), and test. This will tell you if the memory controller if being pushed too far, and we can work on that.
test 3:
set the fclk back to 1600mhz and test. This will decouple the 1:1:1 ratio between fclk, uclk, and mclk, so it's not optimal, but again this will tell us if we might be pushing the infinity fabric too far, and we can then work on that.
make sure when you do each of these tests, that all other aspects are default, except xmp enabled, so that we can target one piece at a time.
I'm not sure which aorus elite you have, so if you can post more detail it may or may not help...
There's plenty more we can try, once we know the above results.
Cheers
