The diff issue is resolved.
ubuntu@nms01:/opt/observium$ sudo svn status
D mibs/wti/WTI-POWER-MIB
ubuntu@nms01:/opt/observium$ sudo svn revert /opt/observium/mibs/wti/WTI-POWER-MIB
Reverted 'mibs/wti/WTI-POWER-MIB'
ubuntu@nms01:/opt/observium$ sudo svn status
ubuntu@nms01:/opt/observium$
ubuntu@nms01:/opt/observium$ sudo svn update
Updating '.':
At revision 10148.
ubuntu@nms01:/opt/observium$ sudo svn diff
ubuntu@nms01:/opt/observium$
Still have these issues:
WTI image logo is something called "DCN"
WTI has no ethernet port, but the power sensors are there and working
Geist has ethernet port but no sensors
Yah, sorry for my mistakes
Fixed now in r10154.