No one in the Immigration office in Chiang Mai can tell you what rule anyone in any other office will apply; they cannot tell you what rule anyone else in that self same office will apply today or what rule they themselves will apply or waive the next time you come; no Farang can tell you anything but his own experiences, and yours will certainly be different, even if you talk to the same Immigration official.
If you look at the websites for the Thai Consulate in L.A. and for the one in Dakka, where is that, Bangladesh? you will find two different lists of papers that you need to bring with you to get a work permit VISA. Plus of course another Farang will tell you that you don't need any of that, just bring a letter from your potential employer and do the rest when you get back.
lt's a little confusing but there are no bad results available so just hang with it, I say. Get a trip to Kuala Lumpur out of the deal anyway, eat some Indian food. Or maybe I'll just go to Burma for 5 minutes next weekend and get another tourist VISA, two months, and get an extension for another month, then get the work permit VISA in L.A. in October when I'll be there anyway.
I must learn to deal with uncertainty.