Boas temps "technically" should be a few degrees warmer than that. Like 82 ish ambient, and 92-94 ish hot spot. Also, their metabolism is much slower. They shouldn't be fed anything that will leave a noticeable lump. They also should only eat every 7-10 days. So warm him up, and smaller prey next time, and proper time between meals. Keep an eye on him, and let us know what happens.
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