WTF did I do wrong? Low ABV rum strip

[Captain Spaulding]

Ok I’m stripping a 5 gallon batch of rum wash, I’ve collected only 1.5 quarts and already coming off the spout ABV is down to 20%. The whole 1.5 qt = 30%.

Recipe: 1 gal Tribute brand equine blackstrap molasses specs TSI 37% dry matter 71% moisture 29% Brix 79.5% (label below).
2 lbs turbinado
2 gallons wonderful smelling dunder that had sat in the yard in a cloth covered bucket for 9 months. Grew a pellicle of green mold but I was able to lift it off the top like a sheet of fuzzy leather. Still smelled great, like roasted orange peel.
Water to make 6 gal (about 1-2 quarts left in bucket after pouring 5 gal into still - see evaporation question below).
Vitamin B, DAP, bakers yeast as usual
Fermented in a room heated to 90F cuz bakers yeast.
Airlock bubbled as expected for 2 weeks but the bucket sat for a few months after that and at one point I discovered the airlock had run dry.
Taste of wash is sour and smell is smoky like hickory smoked ribs. Tastes pretty much what previous washes were like.

Did not measure OG cuz I only had a refractometer and my rum washes always erroneously measure off the scale. Next time I’ll use a hydrometer to measure OG/FG.

So I either did not get enough sugar in it or is it possible the alcohol evaporated through the open airlock???

Stripped distillate has a bit of a plastic burnt smell, not at all like previous successful batches where the recipe was the same but molasses was food grade blackstrap. I don't expect the strip to smell yummy, but this is not a smell I have encountered before.

I still have 3 gal of the molasses. Add more sugar and try again or donate to an equestrian and buy new food grade?
Use the dunder in a new batch or chuck it?
Include the funny smelling strip in a new strip?

F F F!!!!

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