banks in thailand are assholes like that. pretty common for them to tell you to go back to the branch you opened depending on what you have with you. i had to go all the way to ratchayothin to sort mine cus i lost my bank book. even tho i had my passport. but if you've lost it or not planned ahead, that's kinda on you they will say.
I felt confused by contrasting answers so I just rang the thai embassy here and they said you were right. I would've done that the other day, but usually they never answer the phone here. Also, they said the Thai embassy can't approve entry at the moment. It has to go through CDC Thailand (Center for Disease Control prevention).
But thanks for the input guys. The policy just changes a lot.