I don't understand this post , did he get denied entry at immigration whilst trying to enter on visa exempt or did his online tourist visa application get refused or both ?
That's exactly what I thought . There are bound to be people who didn't manage to fill it in due to website problems , Internet problems...etc or simply didn't know about it.
Your first reply says with a METV you can possibly get up to 9 months in Thailand , then your second post mentions possible problems when re-entering if you only spend short entries in Thailand or travel back to back . Surely that's how a METV is supposed to work .