I guess there are many different agents who do this service, but many of my friends used thaivisaservice(.)com I myself used to go on border runs with them but my friends paid for a problem-free entrance via airport two times when they had to switch between student visas, so I know for sure that it works.
it’s not for me to decide if someone needs it😅 I am just sharing the info that this option exists and it works. I did it once myself when I had to leave and re-enter under visa exemption to apply for my second round of ED visa.
I have never seen prices below 3.5k for this particular service 😅 On the islands they ask even more🙈 If you find any agency that offers “an entry with no questions asked” cheaper than 100 USD please send me DM 😅 I need to know too😁
I can only answer to the part of your question, that is - you absolutely can re-enter via the airport with help from “the fast track services” (this is not the same fast track they sell in the airport but I think you know this). It costs an extra ~100USD for Bangkok airports.
I don’t remember if we are allowed to reference specific agencies in this group so you’ll have to do your own research 😅 (I can say that I used the help of the same agency that organized borders to Cambodia, now they changed the direction and go to Laos.
The thing is - they sometimes fail, and if staying undetected is crucial for you, you might want to follow Brandon’s advice.
From my own experience: I used NordVPN, which has a “kill switch” feature that’s supposed to cut your internet connection if the VPN drops, to avoid even a small chance of your real location being exposed. But… it failed me 🤣
In my case, it wasn’t anything serious - I just got blocked from online banking and had to talk to support. But I learned my lesson 😅
To be fair to NordVPN, they apologised for the failure and refunded me without any hassle (though it was still within their 30-day money-back guarantee).
Now I’m with Proton, but I wouldn’t rely on it for anything super important, either.