If it is 777 to 776, then you have nearly two hours. I think it will be doable.
I did a turnaround in June at CGK with LH for the Star 55,555 promotion. LH had even a tighter 'connection.'
After getting out of the plane, I went to the transit desk. They escorted me out of the passport control to the landside checkin area, checked me in and escorted me back to airside. I needed to pay a departure tax. Some people on the same flight went straight to passport control and did check-in themselves and they came back fine. I saw them in a lounge.
All the best.