ASUS RT-AC68U USB tethering not working with Galaxy S8

I can't seem to get my Galaxy S8 to tether with this, it recognizes "Android_mobile" on the network status page but just says "Cable disconnected" on the WAN status. If I toggle usb tethering on the phone it shows the network settings for a brief second "192.168.43.2" but then immediately goes back to "cable disconnected".

I've tried with various firmwares, including stock and merlin, as well as merlin beta. DD-WRT seems to have an out of the box iPhone tethering option but requires a lot...

ASUS RT-AC68U USB tethering not working with Galaxy S8