the rule is you have to be in the country or countries the embassy serves. They are in Indonesia. You are allowed to apply from anywhere in Indonesia, as long as you stay in the country during the application. It's a big country. Most embassies do the whole process online and don't require a physical interview. They emailed the embassy and rescheduled the interview giving time to travel to Jakarta, so obviously that is all fine. You're not being helpful here.
it lists four stamps and the first one, ผ.60, is the most common one that most countries get. It doesn't list an exempt unilateral 90 day stamp I don't think but ผ.ผ.90 which is the Brazil/Korea one. ผ.ผ.30 I think is the bilateral treaty Russia one.
It does mention special screening for certain nationalities that are involved in problems, but as far as I can see the categories of stamps listed are just all the exempt stamps, not one in particular.
Anonymous participant 457 like you say it sort of does depend where you live. I fly out at least twice a year anyway but if you were looking for either the fastest or cheapest option from Chiang Mai, that is a land border run to Laos. Even more so if you were somewhere like Chiang Rai. There is an international airport here but no longer good options for same day return (used be possible to go CNX-KUL-CNX same day).
Anonymous participant 457 there have been several reports already on this group that DTV holders are not being allowed to do land border bounces, either at all, or same day. Some agents can apparently get around this for a fee. Very possibly this restriction on visa holders in the wake of recent changes is not permanent but awaiting clarification, but that is apparently how it is now just in the last few days.
As far as I can see from the actual memo, it very specifically refers to tourist exempt entries, rather than any form of visa. The stuff in the article recommending other visas but not the DTV is interpretation and doesn't seem to be reflected in the memo as far as I can see. It doesn't recommend Elite/PE as good either, but that doesn't mean it's going away. The stamps the memo specifically lists, ผ.60, ผ.ผ.90, ผ.ผ.30, ผ.30 are all very specifically visa *exempt* stamps, as far as I know ผ stamps are unilateral exemptions and ผ.ผ are bilateral treaty exemption stamps (like with Brazil, South Korea, Russia, etc).
what valid reason does OP have? I don't want to be hard on him, but his situation does sound _exactly_ like what they brought this in for. Your son is a Thai citizen with a right to stay in Thailand just sorting out documentation so sure they will be more lenient there.