Death wobble virus HELP

Our Jimny is a new one so we've no issues with that.

However on my Land Rover the "death wobble" is generally caused by insufficient front swivel
preload, worn swivel bearings, or faulty shock absorbers/dampers

Have you checked the shock absorbers?

Did you fit castor correction bushes with the lift? If not then your main problem in insufficient castor angle.

When i bought this lift black raptor said that i dont need castor correctors .. and also the wobble was there before i lifted the vehicle

Oh well if a salesman told you that it must be true!
Lifting the suspension reduces castor angle, and castor angle is there to give the steering stability. You have made it less stable and wobble has increased as a result. It's not the cause, but it will certainly be a reason for it getting much worse. As will the wider and heavier wheels.

Also what did the mechanic do to fix the oil leak on the ball joint? That is a classic sign that kingpin bearings are worn, but people often mistake it for other issues.

So i finally fixed my death wobble problem . Now the car rides like new .. i took it to 3 different steering alignment places  and no one helped me .. the last guy told me that the car since was lifted the pan-hard has sto be adjusted because the previous owner had an adjustable pan-hard ..Also he told me that all the problem was starting from pan-hard bushed and i changed the to polyurethane ones .. also he checked the steering damped and all the components for steering .. He also balanced my wheels and tyres ..Everything now its okay no death wobble at all ..Its like having a new car in the road pretty  smooth  drive