For me there is no extra device connected. I can also confirm that ACPI s3 is not supported.
I didn't test windows 1909 thoroughly, but I did notice that the windows preistalled by asus seem to have the same problem. Just "seem to", since I didn't really use it.
Actually the bug "ACPI s3 is not supported" should raise official attention somehow as well, since there will be users worrying about extra battery usage during sleep. However what bother me most is still that it cannot be waken up from sleep to idle.
And to make it clear, I enabled every wakeup options under linux, even including wake-on-lan, but it still cannot be waken.
Another thing I find strange is that I can hear the noise and feel the heat when it is supposed to be sleeping. This may indicate that kernel actually failed to make it sleep instead of failed to wake it up.
The dmesg I put shows that sth may happen when calling resume_irqs, I am not sure whether it is related or not though. I hope that dmesg may help you debugging both on linux and windows.