Caldera

Apparently, you were of retirement age and the IO saw you as a frequent visitor, so tried to steer you towards a retirement visa. That's a bit over the top with regards to your particular history, but not unheard of.

Is it even worth it to buy a Lao SIM card for a short trip? I've always bought a 7-day data roaming package for my Thai SIM card instead. I'm sorry that I can't give you a definite answer to your question, but knowing how bureaucratic Laos can be, my best guess is that they might well insist on seeing the original. And knowing how inconsistent Laos can be (same as Thailand), it might well be different from one place to the next.

If you're lucky enough not to get shredded by one of their deadly walkways, it's not a bad airport. What I like in particular is that I usually get through much quicker than at Suvarnabhumi.

What a guy, what a country. I need more popcorn.

That's quite a twist. Did he actually study in Korat, or did he obtain that "ED stamp" using an agent without studying?

That's a great way to get rid of conspiracy theorists.

The fewer, the better! Same as with the Chinese and Indians.

If you don't have any other issues besides an inclination to post incoherent rants, consider yourself blessed.

Don't post nonsense. Any overstay in Thailand cannot be resolved without having a valid passport, so there you have your "why". Many reports over the years of people on overstay getting a new passport first, before being able to leave. I don't recall even a single report of anyone being refused a new passport by their home country for being on overstay in Thailand.

Which part of "it depends on the immigration office" do you fail to understand? Whatever you think "the act makes clear" might or might not be interpreted differently by your IO. The OP has no other option than (1) to establish if Ko Samui immigration is willing to fix the stamp, and if so, (2) requires a TM30 receipt to do that. If that's the case and the Airbnb host hasn't filed a TM30 notification, checking into a hotel for a night might be a lot easier than trying to get the TM30 sorted with the Airbnb host.

Again, it depends on the immigration office. It's first and foremost the landlord's responsibility to notify immigration about foreigners staying at their property. When it becomes the tenant's responsibility and what documentation is required isn't consistently handled. Maybe someone can help with specific information for Ko Samui?

That depends on the immigration office. While most would probably agree that a longterm tenant with a lease can file as the possessor of the property, that's a bit of a stretch with a hotel guest.

No. You'd obtain the initial visa as an eVisa back home and your extension(s) at your local immigration office in Thailand.

Will you go back to Bangkok at any point within the 30 days you've been stamped in for? There's no need to get this fixed immediately / next week. I'd try to get it fixed at immigration on Ko Samui first. If they say they can't (or won't) do it, you can still make other plans. A visa exempt entry by air doesn't count against your land border run quota, so you can still re-enter twice overland.

All hail the Emperor.