Hello Ted. I would say that the garlic, butter and oregano slather sounds great!
One issue you ran into maybe the fire management. Sounds like there were a lot of coals for the cook. If you used a whole chimney of unlit and dumped a half chimney of lit on top, you have too much. If you were using briquettes as you mentioned, that contributed as well. Briquettes put off smoke as they ignite. You were kind of using the minion method "on steroids".
I use regular blue bag Kingsford briquettes , and for a cook like that would probably just use a chimney full of lit coals on one side. I would put the chicken on directly to sear it quickly (lid off) and then slide them over indirectly to finish (lid on).
I'm talking about grilling, 45 minutes to an hour, about 400 degrees. 2 hour cook , were you smoking them?
Regardless, never shut your vents all the way down. Your snuffing the oxygen, creating thick, white, bitter smoke.
I have regulated my air flow for years with the top damper. Bottom open. Regulate top. Listening to suggestions from the folks here, have been switching that up and have had good success. Top open fully, regulate bottom. Thank you A-T-S.
Try it. Same cook. Same process. Don't shut down air completely and regulate from the bottom. See what you think. Come back and tell us. Hope it helps!
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