I don't think your ABV is much more than 7.8% which might account for some of the sweetness. Personally I would have taken a more standard route, i.e. chapitalize to 1.090, skip the sorbate, 1/4 tsp. K-Meta per 6 gal, let it sit for a day, pitch your RC-212, MLB at 1.030, wait 3 months, SG-...