Now that is a very interesting and very confusing bottle. I think it may in fact be one of the strangest things I've ever seen posted on here. Did you find anything else alongside it that gives any clues as to what it could be? This one sure raises a lot of questions.
I don't think that's Tibetan, but it does look like some sort of Asian language. Maybe Khmer? Seems to be the closest match I can find at this late hour.
As for clues - it was found in on old village garbage dump that appeared to contain no items dating later than 1920s (like no swastika stuff at all), perhaps even earlier (no Art Deco). This is info from my wife who dug it up with a friend.