Thank you for all the help.
The officers came an hour early and asked for the two "witnesses" who were on their way, everything beurocratic was required, The witnesses Tabien Ban, ID cards plus photocopies, signed witness statements Etc. Including photographs of the witnesses with the applicants inside and outside of the house and showing the gate with the address .
I mention these details as information for those who maybe considering or going to do a "spouse Extension" in Khon Kaen province.