I just downloaded VIM2_Ubuntu-mate-16.04_Linux-4.9_SD-USB_V180207.7z from the Khadas VIM2 Ubuntu Firmware page.
After I burned it to a micro SD card I opened up the /boot directory.
There was nothing mentioning S912 or S905x, just S905.
So I went back to the download page and noticed that the name on the file is VIM_Ubuntu-mate-16.04_Linux-4.9_SD-USB_V180207.
I went back to the Khadas VIM2 Ubuntu Firmware page and downloaded the VIM2 image again, and sure enough, it is the VIM version, not the VIM2 version.
Could you check it and see if I made a mistake or you made a mistake?