By your own, you can only check the fuses and relays to make sure there is nothing burnt/not working, if it is then change those and see if it helps.
More than that checking the instrument cluster for gauge inspection you need to take it to mechanic or rather mechanic first and then electrician.
Seems like the guage is died on you, seek a mechanic and check if they can repair or may be advise who can in Dubai or Sharjah. If not ultimately you got to replace it.
Before jumping on this better check all the fuses and relay are working on it. These electronics are really funny sometime. 2000 dhs problem can get fxied in 50dhs.
It looks like first you should get the gearoil and gear filter changed immediately. If its still jerking in gear shift than show to any gear workshop they can rebuild the gear. There is one in Aweer (ras al khor) main road, when you come from dubai towards hatta on Hatta oman way get into service lane after eppco and keep driving staright and its on ur right hand side, dont know the name precisely. I think its DEXOL.
Better get the full diagnostic done, as in older non ECU controlled cars this seems like a missing issue. But in modern day car it needs to be diagnosed with proper VAG compliant OBDII tool. It may be a as small issue as missing or cyclinder misfiring due to to bad spark plugs, or lead. Or it could be something serious and faulty in gearbox.
You can visit VIP German garage in rashidiya, they are nice and not so expensive like dealers especially for older cars.
Also you can try fw in Al Quoz area behind Time square center.