In short:
Kamado at 250-275f
Short Ribs in for 4-5 hours
The ribs have a layer of meat, then a small layer of fat, and then the meat on the ribs themselves. The top layer gets reasonably soft and edible, but the main chunk of beef is much too chewy still.
I've had two goes at this, the first time the temperature was closer to 300f, and a bit shorter cooking time.
In both cases, I stuck a toothpick in both parts of meat, and it went in as if the meat was soft and tender.
Basically, what am I doing wrong? Not enough time? Not enough heat? I worried that I might overcook them and dry them out. So I might try again, but wrap them in foil halfway through…
EDIT: What I did that worked
First of all, it's a shame that I can mark both answers as answers, because they both helped.
What I did was to smoke the ribs at 270-285f for 5.5 hours, and they were bloody perfect.
I started at 270, and opened the bottom vent enough that the temperatures slowly went up to 280 over those 5.5 hours.
Thanks to everyone for the help.
Edit: And thanks to the user who edited my question and made it worse.
At least learn grammar first, and maybe contact the person asking what their intent is.
Best Answer
Your ribs didn't get hot enough to break down the connective tissue, and the connective tissue is tough. You need to cook the ribs to an internal temperature of 180°-205°F. Don't worry about rendering out the fat; the collagen from the connective tissue provides a moist texture.
I've smoked beef ribs using this recipe: https://amazingribs.com/tested-recipes/beef-and-bison-recipes/smoked-texas-style-bbq-beef-ribs-recipe I smoke them at 250°F until the internal temperature is 205°F. Cooking time varies depending on the thickness of the ribs and whether or not you wrap them. Mine usually take 8 hours without a wrap.