Looking at the instructions, it would seem that tshering was using KSM so nickel would not have been started. You may want to look at the koreader.sh or plato.sh startup scripts to see how they handle killing nickel, sickel, etc.
Plato:
Code:
killall -TERM nickel hindenburg sickel fickel adobehost foxitpdf iink dhcpcd-dbus dhcpcd fmon > /dev/null 2>&1
KOReader:
Code:
killall -q -TERM nickel hindenburg sickel fickel strickel fontickel adobehost foxitpdf iink dhcpcd-dbus dhcpcd bluealsa bluetoothd fmon nanoclock.lua
sickel needs to be killed since it will trigger when the device is not responding. I.e. when nickel has been killed.