No one can say for sure as it’s up to the individual immigration officer you hand your passport to. But 86 days this year plus wanting more isn’t a typical tourist thing and may certainly raise red flags.
To CYA have the three proofs that they may ask for.
1. 20,000 baht (or equivalent) in cash.
2. Proof of accommodation (for the first few days at least)
3. A ticket out of Thailand within the 60 days allowed (you’d probably get away with 90 but your airline may cause issues).
Yes. A multiple re-entry permit allows you to leave/return as many times as you like for the validity period of the permit (your allowed to stay stamp).
Depends on the office you use but you shouldn’t need most of that. You may need the TM30, a filled out TM47 form a copy of your passport photo page and entry stamp and a print of your visa.
Any chance of uploading a picture (redacting personal information) of this? A non O isn’t issued for business reasons. It can be issued for various reasons but business isn’t one of them.
You’re right about getting it changed if that what it says - I doubt that would happen.