Hello Ariel,
thank you for the additional pictures. I think the gonjo was once covered with a sheet from the same material as the pendokok and buntut and reveted at the holes and also at the middle hole for the tang (pesi) and bead over at the crenation visible at the sides of the cross piece (gonjo).
Since you have now dismantled all parts I would advise that you bath the blade and gonjo in lemon acid or pineapple juice (without sugar) until all rust is gone. You can find here many threads how to handle this.
And yes, let test the pendokok material, it will be either gild silver or gold. I would let restore this pendokok, you will have after this a very nice keris, it's worth the effort. Maybe a gold smith can give the gonjo also a new cover!?
A very nice and good keris!
Regards,
Detlef