Front Fork Problem

[Captain_Slash]

Kawasaki suggested replacing this but it means waiting until next week for a replacement with no bike to ride so I got them to replace both leaking seals and put new oil in.
Both seals were blown and the other fork doesnt have this mark on it so am I right to think it wasnt the cause of the seal blowing?
The bike has covered 50,00 km of mainly offroad riding so no complaints, the rear hub is also fucked but a new one is only 1100 Baht and is on order as the bearings dont fit properly now