I have tried three different pools, changing the default settings to the pools specified settings (--groestlcoin instead of -k) I've gone through .bats trying to find out if I could change anything out, and get it to work that way. The --difficulty-multiplier 0.0039062500 say unrecognized option.I've tried your pool, and still no luck.
I'm really not sure about the "groestl kernel" I have a kernel folder in sph-sgminer-groestlcoin folder if that makes any difference at all.