David Broadfoot the story is 4 weeks old. i believe op moved on and not keen to disclose this info. i found it strange that a person in denied entry with just one tourist in passport.
looking at your profile you are a member since 2017, posted many time about border run to Mae Sai and now asking if you cn do a visa application in Vientiane. The answer is yes. Book your appointment on
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and for further info have a look at the Royal Thai Embassy web site.
basically it is just Vientiane and Savannakhet that got strict on visa applicaions. I frequently look at the online system of KL and you can even get slots for the same day. Looks like they are very reasonable.
Benjamin Hays on that I have to correct, Cambodia Airport not allow same day OUT/IN. They request 24 hours in country. At land border they ask a small service fee to forget that requirement.
only the land border count will reset on 1.1.2020. They write manually
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or this year
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. No rule re Tourist, when the Thai Embassy in Vientiane changed that "Lady" was heard shouting "ONE PER YEAR", but this is no rule. Without a remark you could apply for a second within same year, but if they approve is a different story.