Hi
I confirm you can renew "cedula de extranjero" in Santiago.
We did it on November 1st, for my daughter.
You have to go to:
Junta Central Electoral
Local 230, 2do. Nivel, Jardín Plaza, Av. 27 de Febrero, Esquina, Antigua Texas, Av. Padre Ramón Dubert, Santiago De Los Caballeros
You will need to bring:
1. Passport + copy
2. Residencia + copy
3. Cedula + copy
You can pay with bank card.
We were there at 8.46 and out at 9.06.
Really quick and very nice people.
I advice to go there early in the morning.
Hoping this will help other expats.
Have a nice day.