Interesting. RC212 is pretty easy going. I guess the 1118 is insurance. Not that you should take my advice, but I'd probably just pitch the 212.
Hmm, I suspect you are correct that the EC-1118 is for insurance. Note, however, that the expected ABV of this wine is 16%, close to the alcohol tolerance of RC-212. (The document I linked says 16%, but lots of other sources say only 14%.)
Personally, I would reserve a quart of must, and start the rest with RC-212. Then after about 2/3 of the sugar is gone, I would start the EC-1118 in the reserved quart, then add to the rest of the must for any required "mopping up."