[Samsung Galaxy A52 5G] elliwigy:
- My "pseudo" as you call it is a tag/status. I was a "recognized developer" before I became a forum moderator and before jpining the dev commitee. It is tags that every forum moderator receives so ppl can see who the mods are. I am still a developer. The way it is broken down is each device has its own set of moderators which you can usually find a list in each section usually its stickied forwhichever moderators can moderate that section i.e. I can moderate xiaomi forums but since I am not a mod for Samsung I cant moderate in Samsung forums. Rule of thumb though, if you see I have created a thread in say Samsung forum then that is me posting something I have developed or am developing i.e. N9 root method and obviously posting as a developer. You would know if I was posting as a moderator as it'd be saying something in regards to moderation i.e. cleaning a thread for bad language or off topic banter of which I would have deleted/removed comments or some sort of action or if responding to a reported post etc. etc. So it would be clear if I was posting as a moderator as I would make it clear.

- The snapdragon dev section in N9 forum is for all snapdragon models of the note 9. The N9600 is the Korean variant if I am not mistaken and is unlockable by default. The OP in this thread has a USA variant, I did not say all "snapdragon" models were the same. ai simply stated "US/Carrier Models" were not unlockable without a paid service. Since N9600 is not a US/Carrier model it is unlockable and is in that section because it has a Snapdragon chip in it therefore falls in the category of an international model that is unlockable by default and therefore unrelated to the discussion here. The korean variants typically end with a 0. Models that are not unlockable are typically ending with U, U1, or W i.e. N960U, N960U1 or N960W. Anything else is likely not a US/Can model and are typically unlockable by default.

- Afaneh is the other person that can unlock bl's using a paid service which I already stated. USA models can use twrp once they get paid service (given they arent updated to a firmware not able to be unlocked) to unlock the bootloader first. This is the ONLY way to unlock the bootloader. He also makes twrp builds for devices and clearly (as you also included in your link) he is clear that you need to use a paid service. As for that other twrp post I have no idea. Because someone posts in a Snapdragon section and isn't specific on which variants it is for is not against any specific rules. I can bet however without even looking at it you can likely read the comments and see people with US models saying it didnt work or asking how to unlock the BL because it wasnt possible. Typically in those threads the dev will indicate you need to unlock the bootloader first and US variants cannot unlock the BL therefore that TWRP wouldnt apply to them at all.

- As far as your issue, the fact that you could successfully flash custom firmware using ODIN tells me you were unlocked. On locked devices (i.e. US variants) ODIN would fail and device will say an error so they wouldnt even be able to get that far. Samsung always likes to be different in how android and root and stuff work. Sometimes magisk needs to be modified or tweaked to work and sometimes the install instructions vary by device. I cant help you there because I sold my N9 before was able to unlock the bootloader but can guarantee you are able to root your device since bl is unlocked you just have to find the right instructions and follow them to the T. I do not know the steps for your intl model so I cannot say why its bootlooping but I assume you are missing a step somewhere.

As for relocking and getting an OTA, it is possible even if you were still unlocked. OTA will not work however if anything is modified i.e. if you are rooted the ota will fail. Simply having an unlocked BL you can still get an OTA if you havent modified anything i.e. no twrp and no root and no modified rom etc.