they applied for a yearly extension based on raising a thai child and that along with a marriage extension usually gets a home visit during the under consideration period (totally normal thing to have happen)
it has to be what ever the immigration officer at passport control says it needs to be 😮
I have had reports of people standing at the stamp in counter be told by passport control that if they didn't show a ticket back to the country their passport is from within the days they would stamp in for they'd be denied entry.
Those people had to book flights back to their home country right then and there 😕
Now I will agree with you that at a land crossing it is highly unlikely IF a person is asked for onward travel that passport control would insist on return to country of origin
Right and if all you were doing was trying to get a NEW 60 day free entry stamp you should have contracted with a service in your area to take you to the border and back because they have it set up that you get out/back the same day without any issue
That's why services cost much more than you doing it yourself 😕
As I said all you can do is try to come back in, you're not fooling anyone at passport control, they will know at the border you only went to Cambodia to come back to thailand on a new free 60 day entry stamp.
Sincerely good luck with it, that is NOT too hard core of a border crossing, and you should get back in without much issue
seeing as the 19th and 20th are weekend days with the immigration offices closed they have until end of business on Friday April 18th to file in person