It means SD card image yet that support this unit.
Why not, let see if it will work but the first issue that I noticed is that the hashboard of the s9 units is different compared to s9SE hashboard and I believe the s9SE hashboard only supports s9SE control board so my guess is it won't work.
Try to contact
thierry4wd because I heard that he had a s9k/SE modded firmware.
You can check his thread here
S9K Stock firmware SSH unlocked + Control fanI didn't want to, but I went ahead and bought a new miner I got an S9j and is supported by Braiins OS.
Now I'll have to sell my S9 SE.