CarWings does not have a stop charging message. As far as I can tell, the command from the telematics (EV bus message 56E) is pretty simple and made up of a few bit flags.
Code:
hex binary state
86 10000110 idle
46 01000110 status
4E 01001110 cc on
56 01010110 cc off
66 01100110 remote charge
From the highest bit: idle, VCM wake-up logic line status, remote charge, cc off, cc on, unknown, unknown, 0. The unknowns could be 12v supply voltage voltage ok and "within cell coverage"
Since that time I've never seen anything other than these states. You could unplug the TCU and try sending some other things like 0x67: 0110011
1 and see if that turns it off. However, I doubt Nissan would have left this functionality on the table. The only thing that I think they might have left on the table is the code to change the remote turn on temperature. In the 2013+ models this is a command from the AV unit to the climate control computer. I haven't isolated the message on a 2013 but I suspect it *might* work on a 2011 or 2012.
You might look at EV bus message 1F2. I suspect commanded charge power is in here.