I was told by different sources that if another person shares the account then the amount must be doubled, even if that second person doesn't have the DTV or even resides in Thailand
Yeah, this happens a lot unfortunately. I noticed this pattern: if the question is perceived as "obvious" to other people, some of these individuals will assume it should be obvious to the person asking as well, therefore they're entitled to disrespect and even insult. Something I can't find an explanation for, other than these people reflecting unattended personal traumas, most likely acquired in our imposed schooling sistem, which mostly teaches to feel stupid when unable to reply.