I followed your instructions but am getting nothing powerwall-related in emonhub.conf 
I have restarted emonhub.
Log level: debug.
Here is my emonhub.conf entry:
[[PowerWall]]
Type = EmonHubTeslaPowerWallInterfacer
[[[init_settings]]]
[[[runtimesettings]]]
pubchannels = ToEmonCMS,
name = powerwall
url = http://172.16.20.110/api/system_status/soe
readinterval = 10
Using emonSD-17Oct19
Version: low-write 10.2.2
Everything up to date AFAIK.
I’ve probably done something stupid.
Not sure where to start trying to diagnose…