Okay. Anyway, recommending someone to hide she/his working under a DTV so that the person may eventually spend some money with you isn't the wisest and honest. That's just NOT ALLOWED.
Are you volunteering in Thailand? That may be an issue as your DTV doesn't allow you to do it. And that's even more valid if you're getting money from it. You'll need a work permit and the related visa for it (usually Non-B).